This enclaves are a lot of little towns, located along the borders of India and Bangladesh and are a total of 106 of indian enclaves in Blangladesh and 92 Blangladesh enclaves in India. They are the result of a previous war that had fight the Mughal Empire and the kingdom of Koch Bihar, after which war they, apparently, doesn’t seat very well the territory gained and lost. After the partition of India in 1947, what was the Mughal empire unite to East Pakistan, while the kingdom of Koch Bihar started to form part of India.
The desire of both parts to solve this enclave mess situation was state in 1958, but the unratification in time of the Supreme Court of India make that this agreement had to start to beign re-negotiate after the independence of East Pakistan as Bangladesh in 1971. In 1974 both countries agree to exchage some enclaves or at least provide free access to them. This was quickly ratified by Bangladesh, but Indian politician doesn’t paid much attention to this problem
In 2001 they started again with this enclaves case, but the Indians (again) put the problem to the bottom of the cases to solve and it wasn’t until 2011 that an agreement was formalize, with the agreement of India and Bangladesh to exchange 51 Bangladesh enclves for 111 Indian enclaves. Bangladesh rapidly retificates the agreement and India do that on december of 2013.