Jean Stapleton grew tired of playing Edith Bunker for so many years and wanted to leave the show. She had a meeting with co-creator and producer Norman Lear about leaving the show, and when she was asked how she wanted to die she said she didn't care.

So after being Archie Bunker's wife for so long they decided that she would die of a massive stroke while sleeping. The show continued on without her but was never the same.

All in the Family had many spinoff shows the most successful being The Jeffersons which had a long run on TV and helped break down many racial barriers . The Jeffersons can still be found in reruns today

More Info: en.wikipedia.org