Those slippers had nearly caused a diplomatic incident themselves.

I have just completed the thoroughly enjoyable Perilous Fight by Stephen Budiansky, an account of the naval aspects of the War of 1812. Excerpts to follow. Page 30.

“NO VISIT to America was complete for the British traveler of the early 1800s without a letter home laden with disdain for the vulgarity of the inhabitants. Americans were crude, loud, boastful, grasping—and they were ingrates to boot. Augustus J. Foster, secretary to the British legation in 1804, asserted that “from the Province of Maine to the borders of Florida, you would not find 30 men of Truth, Honour, or Integrity. Corruption, Immorality, Irreligion, and above all, self-interest, have corroded the very pillars on which their Liberty rests.” No more than five members of Congress could be considered gentlemen; the rest habitually appeared in “the filthiest dresses.” American women were “a spying, inquisitive, vulgar, and most ignorant race.” President Jefferson himself “is dressed and looks extremely like a plain farmer, and wears his slippers down at the heels.”

Those slippers had nearly caused a diplomatic incident themselves. When Foster’s principal, the new British minister Anthony Merry, came to present his credentials to the president, he arrived in full court dress, sash, ceremonial sword, and all. President Jefferson appeared in an old brown coat, faded corduroys, much-soiled linen, and those worn-down slippers. Merry was sure it was a calculated insult to him personally, and to his country officially. The British minister spent the next several months accumulating imagined insults from other displays of American informality, above all the careless egalitarianism of Jefferson’s hospitality at the White House. Jefferson made a point of dispensing with all the elaborate European rules of precedence of place in seating guests at his dinner table; his rule was what he termed “pêle-mêle”: guests found their own seats. This was all news to Merry, who was mortified when Mrs. Merry was not seated next to the president and he found himself elbowed aside by a member of the House of Representatives as he was about to sit down next to the wife of the Spanish minister. Even an official note from Secretary of State James Madison explaining the customs of his host country failed to convince Merry that it was anything but a premeditated plan to give offense.