Watch out for black flies. To protect yourself wear long sleeve shirts white or brightly colored, thick socks, and long pants tuck the pants into the socks and apply a covering of DEET. Also some type of bug netting in your tent is advised. Flies are most active at dawn and dusk.
talk
There are several small francophone communities in Northern Ontario, however English speaking travellers shouldn't encounter any issues with language since most of those living in these communities are bilingual English-French. There are also many communities that speak mainly Cree, however this is usually on reserves and, once again, there are usually English speakers as well.