Barrett served as Mayor of Milwaukee between 2004 and 2021. In the context of his appointment, Barrett had an official meeting with Grand Duke Henri on Thursday afternoon.

Barrett stated that he is "tremendously honoured and excited to start my next chapter here in Luxembourg as the US Ambassador". Barrett stressed that he is looking forward to "working together as close partners to advance our shared priorities on human rights and climate change, expand our collaboration in finance and space, and defending our common values as NATO allies."

The new ambassador added that he and his wife are "especially eager to meet and connect with Luxembourgers across this small but truly grand country".

The official statement released by the US Embassy specifies that Barrett previously served as the Mayor of Milwaukee from 2004-2021, making him the longest-serving mayor of one of the 50 largest cities in the United States.  From 1993 to 2003, he was elected to serve five consecutive terms in the U.S. House of Representatives. From 1989 to 1993, he was an elected member of the Wisconsin Senate, and of the Wisconsin State Assembly from 1984 to 1989.