Help Poisson Distribution

OguzhanCatal

Doing Physics at University and I have never done poisson distributions.
How the hell do I do it?
The question is...
Show that the data on the number of cavalry deaths in the Prussian Army in the 19th Century are consistent with the poisson probability distribution. The date were accumulated from reports recieved from 10 seperate cavalry corps, yearly, over a 20 year period.
There were: 109 Reports of ZERO deaths, 65 reports of 1 death, 22 reports of 2 deaths, 3 reports of 3 deaths and 1 report of 4 deaths.

Where do I begin? Does it involve drawing a graph?!