In ref to the Mc on the isle of man...
From Irish names to manx: where the adoption of Gaelic names by the Norman lords was I think actively discouraged.
As far as I know there was never any Manx law - the various authors on the Etymology of names look on the change as fairly natural given the effective decoupling of Mann from Ireland - possibly hastened by English scribes who wrote down the name as they heard it though the survival of the ine (daughter) form of some names indicated that the mac/ine was understood and used by many.
Tudor attempted anglicisation of Ireland - esp around the 1570-1600 but a quick look at my history books doesnt show any specific attampt to outlaw Irish names. (there was an outlawing of Welsh around this period - possibly there names were foreably anglicised)
However during the Elizabthan conquest of Ireland the Island kept quiet (though it does appear that the English avoided using the Island even though Elizabeth had assumed control during the disputed Stanley succession) - the English (or rather better I think Lancashire) colonization did not, it appears raise a rebellion until Earl James attempted to impose significant changes in land holding - this lead to the rebellions in 1640's and 50's. It may well be that the Mac's were dropped as part of the anglicisation of the Island which had been going on for about 200 years by the time most surviving Parish registers date from. It may well be that the overwhelming success of the campaign in Ireland demonstrated that it was probably better to align oneself with the English
It is interesting to note that the 1511/1515 manorial roll is virtually 100% mac/ine for Manx names.
By the 1703 composition book probably less than 5% - I have extensive transcriptions for Peel where the mac/ine seems to be dropped between 1570's and early 1600's but at this time most Peel property owners had English names so bit difficult to draw conclusions. Thanks to Wally Corrin there are some transcriptions for Arbory which also show a considerable change around the the same period. Whether this was political (forced or otherwise), or a response to increased communication with England (fears of Spanish invasions, Irish military expeditions etc) I don't know - certainly judging from wills, reported court cases the ine form appeared to last much longer in reported demotic speech.
And so it goes on, and on, oand on...
BUT seriously look into the origin of her name, you may be suprised!
