$10 Fenian Note 1866

I like it! I've seen these from time to time, they were printed by Continental Bank Note Co., an American firm. Interesting that this bond could only be redeemed "six months after the acknowledgement of the Independence of the Irish Nation." So we can presume it was more of a patriotic donation.

Correct, continental did print them. As far as just a donation it actually paid 6% annually. They sold 100s of thousands. The rarity happened because the Irish republic actually opened a spot in New York city so holders could cash them in. It stayed open till well into the 1920s when they closed down after many notices in the newspapers. Almost all got returned for their interest payments making any non returned quite scarce. This one came out of an attic in Maine after someone passed away. Other items show a very rich irish heritage.