While looking up something else in The Civil War Dictionary by Mark Boatner, I came across these statistics on page 495 which I have copied exactly as they appear:
Loyalty of Regular Army Enlisted Men.
Of the approximately 15,000 enlisted men in the R.A. in 1861, only 26 are known to have deserted to the Confederacy at the outbreak of the Civil War.
Loyalty of Regular Army Officers.
In 1861 there were 1,080 R.A. officers in active service; 620 were from Union territory and 460 from seceding states. About 25% of all R.A. officers had been appointed from civil life; the remainder, 821, were West Pointers. They divided as follows:
Stayed Resigned in U.S. to join Army C.S.A Northerners West Point graduates 491 475 16* From civil life 129 129 none Southerners West Point graduates 330 162 168 from civil life 130 1** 129 TOTALS 1,080 767 313 * All of whom had married into Southern families. ** Gen. Winfield Scott(The above facts and figures are from R. Ernest Dupuy, The Compact History of the United States Army, (Hawthorn, NY 1956), pages 122-123. There is a similar summary in Upton's Military Policy.)
Besides General Winfield Scott, other famous southerners who stayed loyal to the Union included, Generals George Thomas, John Gibbon, and Admiral David Farragut.
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