The Mitchell family is a fictional family in the BBC soap opera EastEnders. They were first introduced in 1990, when brothers Phil (Steve McFadden) and Grant Mitchell (Ross Kemp) bought the local garage, the Arches. Since then, they have been developed significantly to include both the immediate and extended families of these characters. McFadden remains as the longest running Mitchell in the show currently, but the family has expanded significantly in the years since, and they still remain a large presence on the square.

Answer this question based on the passage: when did the mitchell's first appeared in eastenders? OK. Let's think. My stream of consciousness:
The relevant information is: They were first introduced in 1990, when brothers Phil (Steve McFadden) and Grant Mitchell (Ross Kemp) bought the local garage, the Arches. The answer is 1990.