This 1867 reference to Michael Trautvetter in St. Louis, Missouri, was actually one that I stumbled upon. I can't say that I was actually looking for him in St. Louis, or even that he was "missing" in a certain range of years in the chronology I had compiled for him. I thought I had him "everywhere." A search for Michael Trautvetter on Fold3 located a reference to the name in their city directory collection. Just because the Michael I was looking for was alive in 1867 and the name was unusual did not mean I necessarily had the same person. I was actually looking for references to another Michael Trautvetter--nephew of this Michael--who was also alive in the same time period.
The Michael who was apparently in St. Louis in 1867 immigrated from Germany in the 1840s and was in Campbell County, Kentucky, in the 1850s and the 1860s. He died in 1869 in Hancock County, Illinois. While he left no descendants, Michael did have family in the Kentucky and Illinois counties where he lived. His interactions with other relatives in those counties ties him to other members of the family. Records of his estate's settlement in Hancock County, Illinois, indirectly indicate he owned property in Campbell County, Kentucky, providing an additional connection.
But St. Louis?
His name appears on page 774 of the 1867 St. Louis city directory with a residence on Cardonelet Avenue.
Trautvetter did not stay in St. Louis very long--he was in Illinois in 1869 when he died there in February of that year. But now I have one more place where I can look for information.
Never assume that your research is complete.