However, the county and the districts remain as administrative regions recognized by various governmental agencies, which gathered vital statistics or disposed of judicial case loads under these geographic subdivisions, and are required to keep the records based on them.

The county was created by the General Court of the Massachusetts Bay Colony on May 10, 1643, when it was ordered "that the whole plantation within this jurisdiction be divided into four sheires".

Named after the county in England, Essex then comprised the towns of Salem, Lynn, Wenham, Ipswich, Rowley, Newbury, Gloucester and Andover.

[2] In 1680, Haverhill, Amesbury and Salisbury, located north of the Merrimack River, were annexed to Essex County.

The remaining four towns within "Old" Norfolk County, which included Exeter and what is now Portsmouth, were transferred to the Province of New Hampshire.

The Massachusetts-based settlements were then subdivided over the centuries to produce Essex County's modern composition of cities and towns.

Essex County is where Elbridge Gerry (who was born and raised in Marblehead) created a legislative district in 1812 that gave rise to the word gerrymandering.

Since 1936, it has trended Democratic, with Dwight Eisenhower in 1952 and 1956 and Ronald Reagan in 1980 and 1984 being the only Republicans to carry the county since.

Essex County includes the North Shore, Cape Ann, and the lower portions of the Merrimack Valley.

The MVRTA is a bus company that connects cities within the Merrimack Valley portion of Essex County.

The following areas of national significance have also been preserved: As of the 2010 United States census, there were 743,159 people, 285,956 households, and 188,005 families residing in the county.

The commission's mission is to promote and preserve the historic, cultural and natural resources of the ENHA by rallying community support around saving the character of the area.