[6][7] In early times the Barisal region was composed of an amalgamation of marshlands formed by the merging of islands brought into existence and built up by alluvial soils washed down the great channels of the combined Brahmaputra-Ganges-Meghna river systems.

The Hindu chieftains from northwest Bengal were dislodged from power and they dispersed over Barisal region and founded the kingdom of Bakla.

However, piracy in this region along the coasts and rivers of southeastern Bengal by Arakanese and renegade Portuguese seamen inhibited any sustained attempts by Mughal governors to push into the Barisal forests.

After 1666, when Mughal naval forces cleared the Meghna estuary of such external threats, the Barisal interior lay ripe for colonization.

Abundant and easily obtainable by purchase from the late 17th century, these grants tended to be regarded by their possessors taluqdar (তালুকদার).

As taluqdars brought their taluqs into agricultural production, these men passed up the land revenue through a class of non-cultivating intermediaries, or zamindar (জমিদার).

For example, in remote Jhalakati Thana in the eastern Bakarganj many of 18th-century pirs and Educationist, Islamic scholars came under the authority, among them named Saiyid Faqir and Faizus Ahmed Khan (A Persian business man and educationist, came for the business trade through Khyber pass and spread education among the Indian sub continent) from wielded enormous influence with the cultivators of the all-Muslim village of Saiyidpur, Hizla and Muladi named after the pirs.

In this situation, one Lala Chet Singh, a captain in the employ of the governor, "succeeded in persuading the Fakir to leave the country."

Today Barisal River port is the most important hub of steamer and motor launch service of Southern Bangladesh.

The division is subdivided into six districts (zilas) and then into 42 sub-districts (upazilas; Rangabali in Patuakhali and Taltoli in Barguna being the most recent).

Lower level administrative areas are 353 union parishads, 3,159 mouzas, 12 municipalities, 25 wards and 4,163 villages.

The main rivers are the Arial Khan, Bishkhali, Burishwar, Tentulia, Paira, Haringhata, Baleshwar, Kirtankhola, Katcha, and Agunmukha.