Leys had also received a commission from the Brussels city administration for a similar program of murals in its town hall but this commission was never commenced due to the untimely death of Leys in 1869 in Antwerp. Leys had a number of pupils. Among these the best-known internationally is Sir Lawrence Alma-Tadema who assisted Leys with the murals in the Antwerp Town Hall. Another well-known pupil was his nephew Henri De Braekeleer (1840–1888). Other pupils were Thomas Simon Cool, Charles Napier Hemy, Willem Linnig the Elder, Petrus Marius Molijn, Hendrik Albert van Trigt and Alexis Van Hamme. Work Henry Leys initially worked in the Romantic style he had learned from Gustaf Wappers with whom he collaborated in the early phase of his career. He treated the typically Romantic subjects, ranging from heroic scenes of war and brigandage to scenes of daily life such as weddings and country festivals. Some of his works show the influence of Paul Delaroche, whom he had met in Paris in 1835. From about 1839, Leys distanced himself from the pathos and historical anecdotes of the Romantic school. He began painting scenes set in 16th-century Antwerp, combining details studied from life with a deliberately archaising style reminiscent of 15th and 16th-century Flemish and German painting. He abandoned the bravura technique inspired by Rubens in favour of line, shape and local colour. Many of the paintings from this period depict specific historical subjects, while others were genre scenes or portraits. This development towards Realism made him one of the pioneers of this artistic movement in Belgium. The painting Wedding in Flanders in the 17th century (1839; Royal Museum of Fine Arts Antwerp) was the first to herald this more sober style. His works from the 1640s attest to Leys' search for historical and psychological truthfulness, which replaced the emphasis on pathos and sentimental anecdote of his earlier work. An example of his works that abandoned historical legend in favour of a realistic depiction of historical events is the composition Albrecht Dürer visiting Antwerp in 1520. Leys based this picture on the account given by Dürer in his own journal of the event. In his scenes of 16th and 17th-century Antwerp, Leys sought to reflect the spirit and atmosphere of that time. His compositions of historical events and of everyday life were realistic and may have been inspired by contemporary French Realists Gustave Courbet and Jean-François Millet.