Help with Military Service

[Elisabeth Humphrey]

I'd like to learn as much as possibly about my  ancestor, Carl Jonsson,  a dragoon who took  the name Wimmergren, living in Kristdala  parish, Kalmar, 1804-1807. Since his death  date is 1807, he apparently died while serving  and I'd like to find out why. Can someone point  me in the right direction, please? Also, will the  records say whether his wife and several  children received a pension or any sort of  financial assistance after his death? I'd like to  know how she survived without his support.   Many thanks,  Elisabeth Humphrey