A couple of years earlier Karl 11th had become of age. So far he had only cared a little about state matters, but now, because of the imminent danger, he became a grown up, ignored the Council totally and undertook the governing himself.

Make this lower case
a couple of years earlier karl 11th had become of age. so far he had only cared a little about state matters, but now, because of the imminent danger, he became a grown up, ignored the council totally and undertook the governing himself.