Before 28th October 1918 there used to be only Hungarian secondary schools on the area of former Kosice county, namely in the cultural centres Prešov, Košice and Užhorod. Since the Slovak patriots felt a necessity to found a Slovak secondary grammar school in the area,they tried to find a town able to fulfill all acceptable quarantees for such an important institution. Finally, shortly after the revolutionary changes the town of Michalovce was chosen in the competition of three Zemplin towns-Humenne, Trebišov and Michalovce.

On the decree of the Ministry of Education of 15th Sept. 1922 the state grammar school was founded in Michalovce using Slovak as an official language. The fact that the day and the month are identical with the date of discovering America seems noticable.

The education started on 11th Oct.1922 in Cintorinska St. However, from the very beginning the school suffered the problems with space. That´s why it was necessary to find a convenient place for building a new shool. It was found at the crossing of Masaryk and Hviezdoslav St. Although the deputy of the Ministry of Education pointed out the close position of brewery (causing smoke and rush) frequent road and high degree of humidity, the position was finally accepted. It was the Prague architect Peter Kropaček who worked out the design of the building. During the time of building the attachment to the school in Cintorinska St. , the Orthodox Jewish society provided three rooms of the Jewish school in Main St.

The basic building stone was layed down 17th November 1928. The ceremony was accompanied with the great cultural event. Dr. Milan Hodza, the Minister of Education, took part in the celebration.

It was on 25th October when the opening ceremony was held and 19th Nov.1931 when the regular lessons started.

Mr Otakar Formanek who had come from the Štefanik real state grammar school in Nové mesto nad Váhom became the first headmaster of the school.

The other members of the teachers' staff were local and chosen as a "substitute " personal solution. The staff consisted of six teachers including the teacher of religion and the headmaster, namely Silvester Jahoda - the teacher of mathematics, Štěpan Pelíšek - geography and biology, Peter Vlk - Slovak and P.E., František Heger - art and calligraphy , Alexander Opitz - Rome - Catholic religion.

During the first year of grammar school there were 39 students, 30 boys and 9 girls. 20 students were Rome - Catholic.

The school results of the first year are charactarized by the data from the first term of 1922/23 : 35% failed. As the reason of the high percentage of failing students is noted a weak preparation in primary schools.

During the years the school was named " The Czechoslovak State Real Grammar School ". This period of school development can be best understood in connection with the idea of united Czechoslovak nation. Consequently, the Czechoslovak language was the official means of communication. Unfortunately, the headmaster of the school had to cope with another problem - the lack of teachers. It was not rare at all that engineers and teachers of local schools had to be employed here. The frequent changes in the teachers' staff meant the real handicap in education. To illustrate the situation, during some years even 10 teachers left the school.

The situation of the beginning of the school year 1926/27 deserves exceptional attention. Due to the lack of teachers on 3.September 1926, there were no lessons and some teachers didn't come to the work without any apology and precising any reason. On 13th.September the teachers staff consisted of 8 members, what was not enough to start a regular teaching basis. The reason of the disinterest evidently stems from the decision of the Ministry of Education to defavour the Slovak teachers by taking them all advantages.The Czech teachers could have been given special payment for their work at Slovak schools. Since this payment was abolished on 14th August 1926, protests and disagreements were the consequence of the situation as it is noted in the Chronnicle of the school.

The staff was of the most part formed by the Czech teachers because of the absence of Slovak intelligence. Later there came the first Slovak teachers. And, so in the year 1934/35 there were two Slovaks (Dr. Hlavac and Gazda) in the 19-member-staff. It is obvious that the first Slovak taught Greek-catholic religion. It was Jan Fedorko who came to teach on 1st.March1925. The first women teachers were Anna Brotanova and Adela Janackova working as substitute teachers.

The opening of the new building is also included in this part of the period. The importance of the event was confirmed by the number of 5000 people attending the opening ceremony.

Number of failing students was quite enormous percentually expressed, from 10% to 30%. In the first part of the year 1932/33 - 43.9% of the students were unsuccessful. The failure could be put down to fatique (many students were coming from homes situated 30 km away from school, and they had to go on foot most part of the journey), helping with house duties. The result at the end of the year 1930/31 was excellent for 60 students, good for 204 and unconvenient for 62 students. The rate between students coming from Michalovce and students coming from the surrounding villages and towns was about 2:3. The behaviour of the students, and especially the criteria of their marking, characterises the result of the year 1934/35 when 355 students had very good behaviour, wellbehaved number of students was 77 and 2 students had to do something with law.

Charity work has been widely connected with the high school. The first supporting activity was made for raising money so that the poor could have been bought new text books. This event took place in November 1922. The country fund gave 2000 crowns to the students who were not able to buy the books. The temporary teacher Jaroslav Korselt ensured dinners for poor students in the wealthy families. Korselt formally worked out and submitted authority the rules of the organisation for support of poor students.

In the school year 1931/32 there were 205 (40.6%) Roman-catholics, 101 (20%) Greek-catholics, 150 (29.7%) of Jewish religion, 17 (3.4%) Evangelists, 22 (4.4%) reformed Evangelists, 5 (0.9%) of Czechoslovak religion, 2 (0.4%) Orthodoxes, 1 (0.2%) Czech Brothers religion and 2 (0.4%)students without any religion. The first school leaving examination on the institution was held from 19th to 21st May (written) and from 23rd to 24th June 1930 (oral). 18 students from 22 passed the examination.

At the end of the first period there were such sad events as the departure of Czech teachers with their families from Michalovce and the Wiennese arbitrage. Without any doubt the Czech teachers contributed with their high qualities to the good reputation of the school.

1939-1945

The name was changed to "Slovak real grammar school". In connection with the Munich events, the building of the school was occupied by the army (mobilisation) at the beginning of the school year 1938-1939. The lessons were interrupted from 24th September 1938 until 10th October.

The idea of national patriotism used to be stressed in education. However , it can't be said that the democratic attributes disappeared entirely. The headmaster of the school was the government commissioner of Michalovce and later he became a leader of Hlinka's Youth. Dr. Hlaváč was the district's inspector of Hlinka's Youth. The members of the staff created new national committee. The Scouts were organised in the school year 1939/40 in Hlinka's Youth (118 boys). In the school year 1941/42 there were already 590 boys and girls organised in Hlinka's Youth. In 1944 the number increased to 694 students.

The lessons used to begin with worshipping Veni sancte and and ended with festive Te Deum. Festive worships were held on 14th March and after them there followed the celebrations of foundation of the Slovak Republic. Pupils participated town meetings. On 13th October one hour was dedicated to the anniversary of the birthday of Dr. Joseph Tisa. The regular radio programme was dedicated to M. R. Štefánik. The school commemorated also anniversaries of P. O. Hviezdoslav, A Kmeť, the Memorandum of the Slovak nation, the foundation of Matica slovenská and at the end of spring there was the Holiday of the Slovak family celebrated.

The minister Matúš Černák, the chief of propagand Alexander Mach, the minister of Education Jozef Sivák, general Čatloš and bishop Gojdič also visited the school.

The considerable attention was naturally devoted to physical education. On Wednesday and Saturday afternoons there used to play school games (mainly volleyball and basketball). When the grammar school was occupied by the army, pupils went to trips and march trainings instead of physical education. The day-long march training used to be 20 km long. The classes competed in long jump, high jump, 60 m run and throwing the disc.

Our school took part in the national competitions - in Bratislava, Banská Bystrica, Žilina. The sportsmen represented their institution very well. The very good sportsman was Jozef Karel who became the winner of hurdle race in Bratislava. With the help of association of the parents there was 100-meter-running-track built in year 1942. The conditions for teaching physical education became worse during the winter 1943-1944, when airraid shelters were built around the playground.

The school made regular public academies in the cinema Capital (later cinema Mier). In the school year 1940-1941 on Wednesdays there was the school radio-broadcasting the rich programme. The man-choir, mixed choir and girl-choir were lead by J. Cibula. The school orchestra consisted of 20 members. The choir of the grammar school sang in the radio of Prešov and several songs were recorded.

Dr. Hlaváč helped the Asociation for support of poor students. He founded the Bibliotheka pauperum, which helped the students coming from the socially poor classes. 2016 books were borrowed to the students in the school year 1938-1939. Poor pupils could board with a reduction in the hotel Zlatý Býk or in the nearby restaurant . Some students got lunches and sometimes also dinners free of charge. For the above the average results in Slovak language Juraj Pado was given 500 crowns from the School Office.

The results from the classification from the school year 1940-1941 are: very good progress - 97 students; good progress - 166 students; satisfactory progress - 312 students; unsatisfactory progress - 135 students. The staff was made of 28 teachers and 3 external teachers of religion.

The structure of students according to the native language in the school year 1938-1939 was: 548 Slovaks,103 Jewish, 34 Czechs,12 Hungarians, 9 German, 1 Russian . There were no students of Israel confession at the end of the school year 1943-1944.

The end of this period is connected with the end of World War II. At the beginning of the school year 1944-1945 the building was occupied by German Army which used it as a hospital.

In the school year 1945-1946 there were 954 students. The outstanding personalities of Slovak cultural life - Dr. Emanuel Böhm, Dr. Ján Fischer, Dr. Alexander Matuška, J. B. Ivan - were the members of the teacher's staff. During the period the school proved its independence - it never celebrated the Hitler's birthday, the victory of German army and there didn't exist any manifestations of racial intolerance.

1945-1958

The chronnicle of the period has not been preserved. The only exception is 1945/46 which is noted by teacher Jozef Štefan. The education was strongly influenced by with the life of society (agitation connected with collectivisation in agriculture). Many of the lesson of social subjects were under strong influence of Communist ideology.The name of the school was changed several times - in 1945 it was " State grammar school ". In 1949 it was " Grammar school of J.V. Stalin " and finally in 1958 "Twelve - years secondary school " specialized in agriculture.

1959-1968

In the school year 1961-1962 the conception of Secondary General-educating School started to be realized. The style of evaluation changed. The percentage of unsuccessful students was in the second term of the school year 1958-1959 7.1% in the classes from 9th to 11th grade but declined considerably. 62 students didn't pass the examination in Slovak language, 63 in maths and 48 in Russian language. It could have been caused by better quality of preparation.

Students participated in summer activities also during the school year. They picked up potatoes, sugar beet, corn (once also in December). The working experience was defined as a revolutionary moment of development of school. Students took part on excursions to Brno, Chemko Strážske and Pozdišovce, where they were informed about production technologies.

The school organized school celebrations and participated on public events connected mainly with the anniversaries of The October Revolution in Russia (VOSR),anniversaries of birth and death of V.I. Lenin and the rise of the Communist Party of Czechoslovakia. With attendance of big number of school youth there were celebrated 1st May, February events, the beginning and the end of the month of Czechoslovak-Russian friendship (28th October). The school remembered anniversaries of significant personalities of the Slovak history, but also 40th anniversary of the Communist Party of Greece, anniversary of Wilhelm Pieck, anniversary of the leader of workers' movement in Bratislava or the other Soviet representatives who are almost forgotten nowadays. Considerable attention was devoted to the International Day of Women (8th March), The Day of Teachers or Welcoming Santa Clause.

1969-1989

The atmosphere of those years was marked by the checks in which the members of the "healthy core" of the party tested the opinions about the staying of the Soviet army in the country and Jan Palach, who committed a suicide by self-burning . They were also testing a stability in materialistic outlook which meant if teachers attended or didn`t attend the religious rites. 15.10.1969 ZČSSP was re-established. Everybody who wasn`t a Party-member was arranged to the IŠP (ideological and political instruction), which development was controlled by school leading and the committee ZOKSS.

The year of party education, seminars like "Lenin and education and Lenin`s message in the Soviet literature " took place in the school, conference about atheist education was realized. The discussions with partisans were frequent. Soviet veteran Fokin came to the school to talk about a liberation of Michalovce. Mutual contacts between pupils and teachers of the lyceum in the Tarnow (Poland) lasted for several years.

Political life was present in the school, mainly in the reports on public Party-meetings, in competitions of the 50th. anniversary of the establishment of Communist Party. Election campaign pairs were persuading citizens about communistic party ideas. Pupils represented the election programme in the communities.The students helped co-operatives by picking the grapes, potates, flax. Brigades were legalized.

The period of normalization had the bad influence on psychology most of the teachers and pupils. They were searching and finding other alternative in work. Radiobroadcasting, painting, photographic, dancing, chess, medical and shooting course, course of beginning authors, literary, philosophical (=atheistic), singing, technical, geographical and sport courses were working. Many of them were informal. School students reached excellent results in different spheres of life in Slovakia and also ČSSR (ČSFR). Levoča reading of poetry and prose competition was won by J.Bulík and B.Šepelová, in the literature competitions Strážnice M.Kudeříkovej was won by L.Benická, first places were won by pupils also in the competition of L.Novomeský (Čeripková, Nadzamová and others). Students reached expressive results in Olympiads in mathematics, physic, biology, geography, chemistry and in computer science (J.Tereščák, P.Vasiľ, Ľ.Šoltéz, P.Pristáš, P.Karailiev, M.Drose, P.Čuchran, P.Matta and others). Class 4.C became the winner of popular radiobroadcasting competition Bluewave. Boys'handball team won in Havlíčkov Brod in the year 1979. In 1981 handball team of boys got the title of master of Czechoslovakia in the competition of secondary schools. The almanach Nový lúč was renewed offering space to the young writers.

From the school year 1969/70 there starts four-year study. On 1.IX.1978 the teaching of computer planning is opened in specialised classrooms. Dr. Michal Lopuch became the headmaster on 1.IX.1978. On 25.XI.1980 the school got the name Gymnázium P. Horova.