After his death in 1791, his only son, Count József Károlyi, inherited the castle, who had the large kitchen in the courtyard converted into a chapel in 1799.

At the time of Count József's death in 1803, an inventory of the Castle showed it to be a one-story building, mostly in good condition, made of burnt brick and had a shingle roof.

A three-turn oak staircase led to the upper floor, the spaces between the turns were laid out with white marble.

The corridors were paved with marble, the double doors were made of oak, the windows had leaded glass panes, and copper fittings.

László Károlyi owned several castles and a palace in Pest,[3] so he sold the little-used residence in Derekegyháza in 1914 to the ammunition manufacturer Manfréd Weiss, who had previously purchased a nearly 9,000-acre part of the estate.

His family spent Christmas and Easter holidays in Derekegyház, but apart from that they only used the castle in the summer and during autumn hunting.

[5] During World War II, during the German occupation, the Weiss family, of Jewish origin, were allowed to leave the country in exchange for handing over part of their property, including the Derekegyháza estate.

[5] After the end of World War II, the castle was nationalized, and, in 1949, became a social home for the mentally disabled.

The castle park, which was 150 cadastral acres in the middle of the 19th century, has now shrunk to 10 hectares, and only a small part of it, around the building, has remained in its original form, the rest is covered in forest.