Can someone please explain to me exactly what the 'OLD GUARD' is/was? When I first re-searched this topic, I got results like, it was a bunch of 60-80 yr old military veterans that were a part of some duck hunting club or something. When I re-search it now, I get all kinds of results, like these for example -

Old Bolshevik

Old Bolshevik, also called Old Bolshevik Guard or Old Party Guard, was an unofficial designation for a member of the Bolshevik faction of the Russian Social Democratic Labour Party before the Russian Revolution of 1917.

3d U.S. Infantry Regiment (The Old Guard) - Official Homepage

The 3d U.S. Infantry, traditionally known as "The Old Guard," is the oldest active-duty infantry unit in the Army, serving our nation since 1784.

Old guard Definition & Meaning - Merriam-Webster

1 : the conservative and especially older members of an organization (such as a political party) 2 : a group of established prestige and influence compare new guard Example Sentences Recent Examples on the Web Sosa, who uses gender-neutral pronouns, said they are motivated, in part, by their own alienating encounter with the medical old guard.