My parklights and dashboard lights flashed off and on, and no response to engine on 1999 Chrysler 300M

I could not start the engine, so I had to disconnect the battery

Asked by for the 1999 Chrysler 300M
does the engine turn over .why did you have to disconnect the battery?
The engine would not turn over, the battery was dead. The next morning I jump-started the car with my other car and everything was normal, I let it run for about a Hour or so to recharge the battery, my question is, what caused it to act that way?
could be a bad battery. check the charging system