Most Embassies have travel warnings or advisories about the southern areas of Mindano in general and specifically the Sulu Archepelligo.

This Australian (ex-soldier) actually lived just 80 miles from Basilan Island, the known stronghold of the Abu Sayyaf and associated kidnap-for-ransom gangs.

If you really must live in such troubles areas, It's usually wise keeping as low a profile as is possible, and especially not to share too many personal details.

By all accounts it seems this guy was not only well known around the area, but it seems he was also a blogger with his own website

"...A website, which could not be immediately verified, advertised a shop run by Warren Rodwell and his Filipina wife in Ipil.
It linked to other sites posting photos and writings from Mr Rodwell travelling around the world."

I don't want to be either negative or an alarmist, but we all need to be aware of our environment no matter where we live.