One other point, like my Dad pointed out this morning, is the speed in which Jackson grew after WWII. Jackson mushroomed, and absorbed a lot of little communites that surrounded it. Fondren, for example, became the downtown subdivision Woodland Hills. Siwell was assimilated, and is now all but extinct, except as a trivia question and a Middle School* in Jackson.
There’s a BBQ house near where I live in downtown Jackson, that has a map of 1950’s Jackson. The northern city limits at that time put the house where I was to be born in a few years at the border between Jackson and the wilds. Now, in 2001, Druid Hill Drive is nowhere near the city limits. They pushed the remaining 6 miles to the country line (North) fast, until running into Ridgeland and Madison County about 1970.
One day, I’m going to do a book on the growth of Jackson. Should be fun. 
*[sub]Middle School = 6th, 7th, and 8th grades[/sub]