The Transcaucasian Democratic Federative Republic (TDFR; Закавказская демократическая Федеративная Республика (ЗКДФР); Zakavkazskaya Demokraticheskaya Federativnaya Respublika (ZKDFR); February – May 1918), also known as the Transcaucasian Federation, was a short-lived South Caucasian state extending across what are now the modern-day countries of Armenia, Azerbaijan, and Georgia.