When did Germany adopt common weights and measures?

Dec 2017
Regnum Teutonicum
By January, 1st 1872, in most of Germany metrification was completed.

When the example of France showed the importance of a good standardized common wights and measures, the process was started. Some places like the Palatinate used the metric system already before 1815 and didn't change it again. The first try of Prussia was to standardize their measurements with the rhenish/rhinelandish foot as basis. Already in 1821 Wuerttemberg made the proposal that all german countries should standardize their measurements and although some action was taken, it didn't come to fruition (some states did a certain standardiziation with each other). The next try by the memebers of the German Confederation ended, because the federation was abolished. A few years later, after Germany formed, it was decided, that the metric system was better and should be the future of all of Germany. On August 17th, 1868 the country decided that metrification had to be done by January, 1st 1872. So the abolishment of century old measurements and weights started in northern and western Germany. The southern german countries decided to follow and started metrification April, 29th 1869 with the goal of finishing the same day in 1872. The only parts of Germany that weren't using the metric system by 1872, were parts that were not part of Germany, yet, e.g. Heligoland.
On May, 20th 1875 Germany belonged to the 12 founding members of the metre convention.