"After the war, Keim continued to report to the Herald from the American Plains; however, his affiliation with that publication ended sometime prior to 1877, according to The Cincinnati Daily Star.

[14] That process was interrupted during the summer of 1870, however, when he was appointed to an investigatory post by President Ulysses S. Grant, and directed to inspect and report back regarding operations at United States consulates in Asia, the Middle East, and South America.

[15] According to historian Charles Stuart Kennedy, "[t]he best overall view of the U.S. consular service after almost one hundred years was provided by De Benneville Randolph Keim."

Engaged in the assignment from August 1870 through December 1872, Keim traveled a total of 47,685 miles while "visiting posts in Japan, China, the Malay Peninsula, Java, India, and Egypt, and on the east and west coasts of Latin America, including the Isthmus of Panama, Ecuador, Peru, Chile, Uruguay, and Brazil".

[16] At some ports I have found gentlemen worthy of the name of consul of the United States struggling under a miserable pittance from the Government, and yet now have the respect of those around them by their personal demeanor.

Almost every consulate had some defects in its history, owing to the incompetency, low habits and vulgarity of some of its officers, during the endless round of evils incident to official rotation.

In China, he discovered that Consul General George F. Seward had enriched himself by keeping the fees from his sale of "licenses to bars and boardinghouses in the American part of Shanghai", diverting the seamen's funds at his disposal to speculative ventures, and "selling the privilege of flying the American flag to Chinese owners of junks, granting them certain immunities and advantages in the river and coastal trade."

Twice wounded—severely—during the Civil War while serving at the commanding officer of the 51st New York Infantry, LeGendre also distinguished himself post-war, in his capacity as consul general, by successfully persuading tribal leaders in Formosa to protect shipwrecked American seamen.

As his inspection tour progressed, Keim noted that the records management and seamen's support services in Java and India were among the few that were being handled appropriately, and that staff at other offices were sincerely trying to "[clean] up the messes left behind by less scrupulous predecessors [and] run straightforward operations with balanced and accurate books", according to Kennedy.

According to historian Mary Simmerson Cunningham Logan, the couple traveled for six months following their wedding, visiting "the localities associated with their ancestral families and nearly all the countries of Europe, extending their journey to Nijni Novgorod, on the Volga.

"[18] They then welcomed the August 1, 1873, and July 9, 1874 births at their Massachusetts home of daughters Elizabeth Randolph (1873–1970), who became the wife, on June 25, 1895,[19][20] of Charles Willauer Kutz, lieutenant-general, U.S. Army Corps of Engineers; and Harriet Virginia (1874–1924), who never married.

[22] As their lives unfolded, his work began to appear in multiple publications, including the Philadelphia Times,[23] while his wife became increasingly involved with the Daughters of the American Revolution (D.A.R.).