Croats of Bosnia and Herzegovina Dalmatian Croatia formed a united Croatian kingdom, which included Dalmatia and part of Bosnia and Herzegovina, Pannonia (eastern Slavonia and northeastern Bosnia), and Savia (western Slavonia). In 1102 Croatia entered into a union with the Kingdom of Hungary. After this, Bosnia, which was earlier part of the Kingdom of Croatia, started to disassociate with Croatia. At first, Bosnia became a separate principality under Ban Kulin who managed to solidify Bosnian autonomy at the expense of more powerful neighbours, but only in the 14th century did Bosnia become a formidable state. In the 14th century, King Tvrtko I conquered part of
Agreement on Friendship and Cooperation between Bosnia and Herzegovina and Croatia Community of Herzeg-Bosnia (HZ-HB) was established, it claimed it had no secessionary goal and that it would serve a "legal basis for local self-administration". It vowed to respect the Bosnian government under the condition that Bosnia and Herzegovina was independent of "the former and every kind of future Yugoslavia." In December, Tuđman, in a conversation with Bosnian Croat leaders, said that "from the perspective of sovereignty, Bosnia-Herzegovina has no prospects" and recommended that Croatian policy "support for the sovereignty [of Bosnia and Herzegovina] until such time as it no longer suits Croatia." In April 1992, the siege of Sarajevo began,