There is one thing puzzling me.

In the 1900's my Great Grandparents changed their names from Arsenault to Arnold then back to Arsenault.

In the 1930's My Grandmother changed the names of herself, my dad and my aunt from Arsenault to Arnold back to Arsenault.

In the 1950's my Grandfather Legally Changed his and his 2nd wifes name from Arsenault to Arnold. They kept it at Arnold.

Would anyone happen to know why all the name changes back and forth???

Thank you again for all your help.
It is very much appreciated.

prince edward island was at one time a french posession,when england became the dominating force and with it many people used english versions of their names,i.e. poirier became perry.arseneault became snow .also census takers and clergy changed the names as they did not speak french.often,people would use both versions of their names until it became a legal issue

No Arsenaults that lived in PEI changed their name from Arsenault to Arnold. But some who emigrated to the USA did change. In some cases it was imposed on them. For some, it was voluntary to better intergrate in the anglophone society and easier to find a job.