The Armenian Kingdom of Cilicia (Middle Armenian: Կիլիկիոյ Հայոց Թագաւորութիւն, ), also known as Cilician Armenia (Կիլիկեան Հայաստան, ), Lesser Armenia, Little Armenia or New Armenia, and formerly known as the Armenian Principality of Cilicia (Կիլիկիայի հայկական իշխանութիւն), was an Armenian state formed during the High Middle Ages by Armenian refugees fleeing the Seljuk invasion of Armenia. Located outside the Armenian Highlands and distinct from the Kingdom of Armenia of antiquity, it was centered in the Cilicia region northwest of the Gulf of Alexandretta.
The kingdom had its origins in the principality founded c. 1080 by the Rubenid dynasty, an alleged offshoot of the larger Bagratuni dynasty, which at various times had held the throne of Armenia. Their capital was originally at Tarsus, and later moved to Sis. Cilicia was a strong ally of the European Crusaders, and saw itself as a bastion of Christendom in the East. It also served as a focal point for Armenian cultural production, since Armenia proper was under foreign occupation at the time. Cilicia's significance in Armenian history and statehood is also attested by the transfer of the seat of the Catholicos of the Armenian Apostolic Church, spiritual leader of the Armenian people, to the region.
In 1198, with the crowning of Leo I, King of Armenia of the Rubenid dynasty, Cilician Armenia became a kingdom. In 1226, the crown was passed to the rival Hethumid dynasty through Leo's daughter Isabella's second husband, Hethum I. As the Mongols conquered vast regions of Central Asia and the Middle East, Hethum and succeeding Hethumid rulers sought to create an Armeno-Mongol alliance against common Muslim foes, most notably the Mamluks. In the thirteenth and fourteenth centuries, the Crusader states and the Mongol Ilkhanate disintegrated, leaving the Armenian Kingdom without any regional allies. After relentless attacks by the Mamluks in Egypt in the fourteenth century, the Armenian Kingdom of Cilicia, then under the rule of the Lusignan dynasty and mired in an internal religious conflict, finally fell in 1375.