Sylhet District was created in 1772 after this area was acquired by the British in 1767 and Mr. William Thackeray was appointed as the first collector.

Sylhet District was established on 3 January 1782, and until 1878 it was part of Bengal Province under Dhaka Division.

[5] According to 2022 Census of Bangladesh, Sylhet district had 746854 households and a population of 3,857,123, 26.25% of whom lived in urban areas.

Sylhet district had a literacy rate of 76.43% (for 7 years and above), compared to the national average of 74.80%, and a sex ratio of 96.74 males per 100 females.

The rainy season starts from April to October and it is so hot and humid with very heavy showers and thunderstorms almost every day, whilst the short dry season starts from November to February and it is very warm and fairly clear.

The physiography of Sylhet consists mainly of hill soils, encompassing a few large depressions known locally as "beels" which can be mainly classified as oxbow lakes, caused by tectonic subsidence primarily during the earthquake of 1762.

Geologically, the region is complex having diverse sacrificial geomorphology; high topography of Plio-Miocene age.

Available limestone deposits in different parts of the region suggest that the whole area was under the ocean in the Oligo-Miocene.