The department's history is written with important facts, which show the social and economic development of San Miguel, also known as "Pearl of the Orient". Lenca culture flourished here. When the Spanish arrived in the eastern Uluas encountered the indigenous. On June 12, 1824 San Miguel was appointed as an independent province of the Mayor of San Salvador and was given the name that is known today.
• On May 8, 1530 was founded the city of San Miguel by Don Pedro de Alvarado.
• In 1763, the volcano Chaparrastique made its first eruption.
• On July 15, 1812, the General and Extraordinary Cortes granted to the department head the title of "Very Noble and Loyal City".
• On March 12, 1856 the city was destroyed by fire.
• In 1862, General Gerardo Barrios began construction of the cathedral.
• In 1874 San Miguel became the first telegraph line.
• On September 15, 1892 was introduced electric service.
• On December 31, 1909 the theater opened.