Between the German navy’s foundation in 1848 and the present day, it went from initial reliance on USN assistance, to twice attempting to cut Atlantic shipping routes between the United States and Europe, to a cooperative relationship between the two navies built on mutual trust.
"German Navies from 1848 to 2016: Their Development and Courses from Confrontation to Cooperation,"
Naval War College Review: Vol. 70
, Article 3.
Available at: http://digital-commons.usnwc.edu/nwc-review/vol70/iss4/3