Memelland
The congregations in the "League of Nations mandate of the Klaipėda Region" () continued to belong to the . When from 10 to 16 January 1923 neighbouring Lithuania conquered the mandatory territory and annexed it on 24 January, the situation of the congregations there turned precarious. On 8 May 1924 Lithuania and the mandatory powers France, Italy, Japan and the United Kingdom signed the Klaipėda Convention, granting autonomy to the inhabitants of the Klaipėda Region. This enabled the "Evangelical Church of the old-Prussian Union" to sign a contract with the Memel autonomous government () under Viktoras Gailius on 23 July 1925 in order to maintain the affiliation of the congregations with the "Evangelical Church of the old-Prussian Union".