Where's the “controversy” coming from? The Left, of course.
Yes, Serra was a zealous missionary and he “took away” ancient Indian cultures from the natives of California.
But, just what was that “culture” other than living like animals, day to day, with no future and never traveling more than one day from where they were born. Crouching in the rain or starving when there was none. Being fodder for the massive Grizzly Bears that freely roamed the area.
All they had to look forward to from the day of their birth was hardship leading to eventual death. Father Serra and his fellow missionaries gave them filled bellies, relief from harsh weather – and the hope that there was something more to life than just dying and ending it all.
Anyhow, the story is @ http://americamagazine.org/issue/controversial-canonization