I have just come across a link to the 1641 Depositions held in Trinity College Library in Dublin Ireland. These were statements mostly by Protestants regarding the rebellious activities of Irish Catholics around the time of the Oct 1641 rebellion where the rebels attempted to take over Dublin Castle.
There are a number of Fannings mentioned in them different depositions. The surname is spelled Ffanning, Fanning or FFanninge.
It is possible to look at the original often illegible documents. But there are also transcripts of these papers below which is just as well.
So far I have come across Edmond Ffanning in 1642, Dominick Ffanning 1646 and a John Ffanning 1642. Dominick Fanning, the Mayor of Limerick, who was executed by Cromwell features in many as a rebel.
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The link is 1641 Depositions.