This does not match in form or style any polearms I’ve run across... which is not unusual in the polearm world.
The blade appears heavily influenced by post-17th century sword blades, and the attachment method obviously resembles European polearms for many centuries.
Since design is often a result of usage/function, the upturned tip would imply it was designed after armor had gone out of style. It does not appear to be a copy of another design, but a combination of two.
Unregulated or unique lower end polearms are often attributed (rightly or wrongly) to locally blacksmithed militia weapons or general “peasant revolt” weapons.
Whatever it is, I believe it is “real” and purposefully built as a weapon.
I would venture to guess it’s mid-18th to mid-19th century. I usually see the unusual/“peasant” polearms of this period associated with Ireland, Scotland, and France... but those determinations are likely solely a function of where the item was discovered in an attic versus any inherent design assumptions.
This is my opinion, which is worth what you paid for it.
