United Kingdom
From Halopedia, the Halo wiki
The United Kingdom of Great Britain and Northern Ireland (U.K. or United Kingdom) is a political entity made up of the unified Kingdoms of England and Scotland, the principality of Wales, and the six historic counties of Northern Ireland. It hosted Jake Courage’s museum pieces, a ground-breaking British war photographer.[1]
The unified state has made many contributions which even the 26th Century UNSC used, such as heavy industry, military organization, constitutional law and the World Wide Web, of these the UNSC either kept unchanged or evolved for their own purpose.
Michael Baird was from the United Kingdom, specifically Scotland.