First Essex

Eastern National was the dominant bus company that operated in Essex from 1929 to 1995. It was nationalised in 1949 and became part of the National Bus Company in 1969. It was later privatised in a management buyout in October 1986. In April 1990, Eastern National was acquired by Badgerline, which divided the company into two brands: Thamesway in the south of Essex and LRT tendered routes; with the Eastern National name retained for operations in north Essex and south-east Hertfordshire.

The two companies were included in the June 1995 merger of Badgerline with GRT Group to form FirstBus, which then recombined the two operations and renamed the company First Essex. Little changed initially for passengers but, gradually over the next decade, First introduced its nationwide corporate branding which eventually led to the demise of the Eastern National and Thamesway names.

First Essex was criticised by passengers and members of the Southend Area Bus Users' Group for withdrawing services which it considered no longer economically viable when Southend Borough Council withdrew bus subsidies as part of budget cuts in 2005. First said it was due to low passenger numbers, even when parts of the route were profitable. Further criticism came from passengers when First Essex and Arriva Southend decided to withdraw their Day Rover ticket, which allowed unlimited journeys on the day of purchase on buses operated by both companies, regardless of which issued the ticket; as a result, their day rovers could only be used on the buses of the company that issued them. They replaced it with a more expensive Octopus ticket, which can be used on any service buses in the general Southend area.

In March 2023, FirstGroup purchased Ensignbus, which ran bus services in Essex, as well as a vehicle refurbishment and resale operation. It was expected that its bus service operations would remain separate from those of First Essex. At the time of acquisition, Ensignbus had a young vehicle fleet of 55 buses.