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
Federation of Bosnia and Herzegovina and Bosniaks ended with mediation by the United States and the signing of the Washington Agreement on 18 March 1994. The cooperation between Croats and Bosniaks was renewed, and the Federation of Bosnia and Herzegovina, a Bosniak and Croat controlled area was established. There was also a proposal to create a confederation of Federation of Bosnia and Herzegovina and Republic of Croatia. The joint command of ARBiH, HVO and Croatian Army (HV) was established in March 1995. The closer cooperation between Croats and Bosniaks was made through the Split Agreement where Bosnia and Herzegovina's Muslim leaders allowed the Croatian Army