Dagestan (; Russian: Дагестан, romanized: Dagestan), officially the Republic of Dagestan (Russian: Республика Дагестан, romanized: Respublika Dagestan) is a republic of Russia situated on the Caspian Sea, in the North Caucasus of Eastern Europe. It is located north of the Greater Caucasus, and is a part of the North Caucasian Federal District. As the southernmost tip of Russia, the republic shares land borders with the countries of Azerbaijan and Georgia to its south and southwest; and borders the Russian republics of Chechnya and Kalmykia to its west and north, while having a border with Stavropol Krai to its northwest. Makhachkala is the capital and largest city; other chief cities are Derbent, Kizlyar, Izberbash, Kaspiysk and Buynaksk.
The republic covers an area of 50,300 square kilometres (19,400 square miles), with a population of over 3.1 million residents, of more than 30 ethnic groups and 81 nationalities. It is one of the most linguistically and ethnically diverse, as well as the most heterogeneous republic of Russia. The residents of the republic mostly speak North Caucasian and Turkic languages; however, Russian is the primary language and the lingua franca in the republic.