Béla Kéler (13 February 182020 November 1882) was a Hungarian composer of romantic music period and orchestral conductor. Béla Kéler was born as Albert Paul Keler (Adalbert Paul von Keler). He is also known in Hungarian as Kéler Béla. He was born Bártfa, Sáros County, Kingdom of Hungary, Austrian Empire (present-day Bardejov, Slovakia), and died in Wiesbaden, German Empire. He was active in Hungary, Austria and Germany.

Family Béla Kéler was born in 1820 in Bártfa (, present-day ), Kingdom of Hungary, as Albert Paul Keler, but German and Austrian sources also give Adalbert Paul Keler. He descended from an ethnic German family on his father's side, but was ethnic Hungarian on his mother's side.

His father Stefan Kéler (17811849) was a principal magistrate of Bártfa, from an old Bártfa burgher's family. His mother Anna Bóth (17931848) was from the Hungarian Both de Botfalva noble family. They raised 13 children. Albert's siblings were Frederika, Stefan, Emilia, Antonia, Matilda, Augusta, Apollonia, Ferdinand, Viktor, Josefina, and Amalia. The household was German speaking; the majority of residents of Bártfa that time were Carpathian Germans.

Youth Kéler's musical education starts with Franz Schiffer a choirmaster at the Bardejov Basilica of St. Giles, who taught him the basics of the violin and piano. Children from evangelical families in Bardejov, to which Kéler belonged, went to a German school by the evangelical church. Kéler completes his basic education in 1834. In the same year he was confirmed. He continued his studies at the Lutheran lyceum in Levoča (1834–1835) and following this, at the Evangelical College in Prešov and the Debrecen Reformed College (1836–1840).

While studying law and philosophy in Prešov, Béla Kéler led the school orchestra and wrote smaller compositions, however his parents preferred that he would continue in the family legal profession tradition.

The difference between the vision of Béla Kéler and that of his parents led to a situation where, at their wish, he started, on July 1, 1840, one year of practical training in agriculture at the estate of the Counts Schönborn-Buchheim in Mukačevo. Even while performing hard physical labour, Kéler did not cease to strive for an artistic future. After the end of his one-year engagement in Mukačevo, Kéler left to work at the farms of his brother-in-law Ferdinand Medwey, the husband of his sister Amalia, in Galicia in Beskids. As a result of natural disasters and fires, his brother-in-law Ferdinand lost his property so Kéler lost employment and returned to Bardejov. He spent the summer of 1844 with his parents at their villa in Bardejovské Kúpele. Kéler offered several of his waltzes to the conductor of the local spa orchestra who included them in the colonnade concert program. During the autumn of that year, Kéler moved to Prešov where he was soon able to teach music and perform in the local theater orchestra.

Career 1845–1860 Violinist at the Theater an der Wien (1845–1854) After less than a year of engagement in Prešov, Kéler moved to Vienna where the owner-director of the Theater an der Wien, Franz Pokorny (1797–1850), engaged him from August 28, 1845, in the position of a violinist in his orchestra. The still existing theatre got its name from the river Wien which runs underground beside the building. Besides performing as an orchestral violinist, Kéler studied for two years harmony and composition with the Theater an der Wien violoncellist Carl Schlesinger and in 1851–1853, harmony and counterpoint with the pedagogue at the Vienna Conservatory Simon Sechter (1788–1867), among whose students were the composers Franz Schubert and Anton Bruckner. Kéler's nine-year long engagement with the Theater an der Wien orchestra officially ended on May 7, 1854. During this period, his first ten opus numbers were published. The first of these is the composition "Three Hungarian", Op. 1, published by the Vienna publisher Tobias Haslinger in 1846. The pivotal composition for Kéler's further career, especially conducting, became the waltz "The Stars of Hope", Op. 17. Johann Benedict Sommer asked Kéler to send him this waltz for an orchestral performance at Sommer's salons in Berlin. Kéler sent him the waltz in July 1853.

Conductor of Sommer's Orchestra in Berlin (1854–1855) A year later, due to the success of his waltz "The Stars of Hope", Op. 17, with the Berlin public, Kéler was engaged by Johann Benedict Sommer for the chief conductor's position in his 36-piece orchestra. Concerts took place almost daily in Sommer's salons which occupied today's railway station on Potsdam Square. Kéler's five-month contract covered the period of May 1 to October 1, 1854. Kéler's Sommer engagement lasted significantly longer than the originally planned five months, actually until the autumn of 1855. Kéler led the Sommer orchestra not only in Berlin, but also in Hamburg, Dresden, Wrocław, Cologne and other concert venues. As part of the eleventh concert of Sommer's orchestra in Hamburg, Kéler introduced the premiere of his extensive vocal-instrumental composition The Carpathians for tenor, male chorus, orchestra, and recital on October 5, 1854. In the autumn of 1855, Kéler parted with the Berlin orchestra and returned to Vienna.

Conductor of Lanner orchestra in Vienna (1855–1856) Following the untimely and unexpected death of August Lanner in September 1855, the orchestra found itself without a conductor. Several candidates vied to take over the Lanner orchestra. Finally, two persons were entrusted to lead it. Béla Kéler and its current concert master Jakob Haag (1823–1874). Both conducted most of the concerts during the 1855–1856 season. From today's knowledge, it is not possible to determine, whether Kéler's seven-month engagement in Vienna was agreed to beforehand as a short-term fill-in until the end of the concert season after the sudden death of August Lanner, or it was ended after Kéler was made an offer from Count Mazzuchelli for the post of a bandmaster with his military regiment.

Bandmaster of the Count Mazzuchelli Regiment (1856–1860) In Vienna on August 1, 1856, Béla Kéler was appointed to the post of a bandmaster of the Count Alois Mazzuchelli (1776–1868) 10th Infantry Regiment orchestra. This appointment presented a major challenge to Kéler. He had to be artistically creative under demanding military conditions, despite the fact that the regiment often had to move around. It moved successively through Vienna, Debrecen, Budapest, Belgrade, Sibiu, Portogruaro, Valvasone, Brasov and other cities. Kéler's orchestra, which apart from the wind instruments included string instruments in order to perform not only at military events, but at individual promenade concerts, where marches were supplemented by dance compositions, transcriptions of operatic works and medleys of popular melodies, so called potpourris. The proof of the quality of Kéler's work with orchestra is the winning of "Mazzuchelli March", Op. 22, in a competition organized by the Austrian military bandmaster Andreas Leonhardt in 1857. The march, which was dedicated to Count Mazzuchelli, was for almost the whole 20th century wrongly credited to the Austrian composer Anton Bruckner (1824–1896). As late as 1977, the march under the title of "Apollo March" appeared on the list of Bruckner's works with the number 115. The error was probably caused by the fact that Kéler's "Mazzuchelli March" is similar in its form and instrumentation to Bruckner's Military March in E-flat major, WAB 116, it seems that Bruckner was inspired by the "Mazzuchelli March". In March 1857, Kéler appeared with his orchestra at the Debrecen theater, housed in the granary belonging to town counsellor Gábor Nánássy. With a short exception at the beginning of 1859, when the regiment was in Belgrade, Kéler's regular concerts in Budapest took place until the end of April 1859. In May 1859, Kéler as military bandmaster, moved with the regiment for manoeuvres by the Austrian army to Italy, where the so-called Second Italian War of Independence was being fought between the Austrian and Sardinian-French armies. After the conclusion of this battle, which saw the loss of the Austrian army in the Battle of Solferino at the hands of the Sardinian-French armies, his service with the military orchestra brought Kéler to Sibiu in Romania. The work for the military regiment was physically very demanding for Kéler, and likely had a negative impact on his later serious health problems. Already during his service, he had undergone several cures in the Romanian spa town of Oradea. In 1860, he requested to be released for health reasons. This was accepted, and he ended his service in the army on September 30, 1860.

1861–1872 Conductor of own orchestra in Budapest (1861–1862) Kéler spent the second half of 1860 and the first months of 1861 in Bardejovské Kúpele, in Prešov and at other locations in his native region. From here, he headed for Budapest where, together with Josef Dubez (1824–1900), who was active until 1860 as a bandmaster of the 4th Infantry Regiment Hoch-und Deutschmeister, founded an approximately 30-member orchestra. Kéler headed this from March 1861 to the end of 1862. Towards the end of 1862, an offer was received by Kéler from the Duke of Nassau for a long-term engagement as an orchestral conductor for his regiment in Wiesbaden. Since Kéler preferred permanent engagements to uncertain freelance work without a regular income, he decided to accept the offer and to discontinue his work at the head of his own orchestra. On December 21, 1862, the last Kéler concert took place in Budapest.

Music director of the 2nd Regiment of the Duke of Nassau (1863–1866) In January 1863, Béla Kéler took over the post of the court bandmaster of the 45-member orchestra of the 2nd Duke of Nassau Regiment in Wiesbaden (1817–1905) after Benedict Stadtfeld (1788–1878) who retired at the age of 75. The regimental commander was Bruno Neidhardt von Gneisenau (1811–1889). Kéler conducted the major part of the concerts by the orchestra of the 2nd Regiment in the spa building in Wiesbaden, since a permanent spa orchestra did not yet exist at that time. The programme of Kéler's concerts consisted not only of his own compositions and dance pieces by some of his contemporaries, but also symphonic creations by Haydn, Mozart, Beethoven, Mendelssohn-Bartholdy, Schubert, Berlioz, and others. An inseparable part of the concerts were the overtures by the romantic composers – Verdi, Rossini, Gounod, Donizetti, Weber, and others. In 1864, Kéler conducted 317 concerts. His overall annual income increased to around 3 000 gulden. Kéler remained in the position of bandmaster of the 2nd Regiment Orchestra until November 1866, when the Duchy of Nassau was annexed by Prussia after the defeat of the Austrian Empire in the Prussian-Austrian War. Duke Adolf was removed from the throne and Nassau military units were incorporated into the Prussian army.

Mainz, Bardejov and Amsterdam (1867–1868) In the years 1867 to 1870, Kéler did not have any permanent engagements. He lived in rental accommodation in Wiesbaden, first at Michelsberg 23, and later at Marktstraße. In January and February 1867, Kéler conducted the Wiesbaden spa orchestra at carnival concerts in the historical Frankfurter Hof Hall in Mainz. Every Sunday and during holidays, he performed at concerts in the Wiesbaden Saalbau Schirmer.

In July and August 1868, Kéler was staying in his native Bardejov region. On August 4, he organized, in cooperation with Count Ferencz Szirmay (1838–1871), a benefit concert in Bardejovské Kúpele in the aid of victims of a June fire in Bardejov, during which tens of houses burned down.