Moldova is a landlocked country sandwiched between Ukraine and Romania. Like its immediate neighbors, Moldova is a borderland state contested between Russia and the West. Moldova's small size, flat terrain and strategic location on the Bessarabian gap has made it vulnerable to invasion and control by outside powers throughout its history. The territory that now makes up Moldova was contested between the Ottoman and Russian empires in the 19th century. In the 20th century, the Romanians, Germans and Soviets fought for control over its territory. When the Soviet Union collapsed in 1991, Moldova became an independent state for the first time in modern history, with its economic, political and demographic core located in the capital of Chisinau. Independence has not removed external competition for influence over Moldova. The country's political system is roughly evenly divided between pro-Russian and pro-European Union groups that clash — sometimes violently — over the country's orientation toward Moscow or toward the West. Moldova is also divided geographically, with the territory of Transdniestria breaking away from Chisinau's control in the wake of the collapse of the Soviet Union. Transdniestria remains de facto out of the control of the Moldovan government and is supported financially and militarily by Russia. Coping with these various internal and external divisions is Moldova's primary geographic challenge.