Kaschlan, Kastellan or Kurrhahn was a simple card game related to the Russian game Durak or German game of Hund. It is for two to five players (four best) and may be played with a Skat pack of 32 French- or German-suited playing cards or a standard 52-card French pack.

The origin of Kaschlan is not certain but it seems to have surfaced in German East Prussia in the early 19th century. In 1882, Frischbier describes Kaschlan as "a popular family game in which the Kaschlan, Kaschlansche or Kaschlanka, Polish kasztelanka, (Queen of Diamonds), is the highest card." Thus the name, both of the game and its top trump, comes from the Polish kasztelan which means "castellan" and its resemblance to Durak suggests that it may have been originally Polish or Russian. Nevertheless, by the mid-19th century, it was a popular Prussian card game, especially among children and women, and was well known enough to lend its name to Prussian idioms. For example, der Magen spielt mit dem Darm Kaschlan meant, literally, "my stomach's playing Kaschlan with my bowels" i.e. "my tummy's rumbling" or "I'm hungry". Näs' on Muul spiele Kaschlan (in Danzig: Kurrhahn, "turkey" or "irascible person") meant "[his/her] nose and mouth are playing Kaschlan" and referred to old people who had lost their teeth and so their nose and chin were so close that they appeared to move together.

The game is not recorded in German gaming compendia and, by 1873, was described as "no longer common" in Danzig, West Prussia, but was still "a well known game of chance" in East Prussia in 1888. Nevertheless, references to it continue to appear during the early 20th century. Frischbier records that there was often a lot of cheating to avoid becoming the "Kaschlan", a nickname for the loser.

Playing cards marketed inter alia for Kasztelanskie were still being produced in Poland in 1972.

The game is played with a normal Skat pack of 32 French-suited cards. If German playing cards are used, the Obers replace the Queens and the Unters the Jacks, as normal. The Queen of Diamonds, the Kaschlan, is the commanding card and the only permanent trump. Apart from that, cards rank in their natural order: A > K > Q > J > 10 > 9 > 8 > 7.

Historically it is recorded that the game was also played with a 52-card pack. There were also 24-card packs sold in Poland for Kasztelańskie.

The game is like a simple variant of multi-player, cut-throat Durak. The following rules are based on Illig:

The aim is to shed one's hand cards as quickly as possible. The last player left holding any cards is the loser.