East Cobb is an unincorporated community in Cobb County, Georgia, United States, with a population of 164,055 people. The area was developed as a suburb of Atlanta beginning in the 1960s. In contrast to other northern suburbs of Atlanta, East Cobb has remained unincorporated. Residents of East Cobb typically hold a Marietta add…East Cobb is an unincorporated community in Cobb County, Georgia, United States, with a population of 164,055 people. The area was developed as a suburb of Atlanta beginning in the 1960s. In contrast to other northern suburbs of Atlanta, East Cobb has remained unincorporated. Residents of East Cobb typically hold a Marietta address, although they are outside Marietta city boundaries.