 Complete the following phrase:  Since 1866, the four chartered provincial governments made a move towards coordination and cooperation by designing a number of common projects. At San Sebastián, the Spanish General Prim ratified in 1869 his position in favour of the distinct status held by the Southern Basque Country the Sister Provinces conditioned on their unambiguous attachment to Spain. However, the general was assassinated in the midst of political instability 1870, and soon on the 