Complex sentence: After attempting in vain to gain backing from several Arab governments, including both Algeria and Morocco, but only drawing faint notices of support from Libya and Mauritania, the movement eventually relocated to Spanish-controlled Western Sahara to start an armed rebellion.
Split into simpler sentences: After attempting in vain to gain backing from several Arab governments, including both Algeria and Morocco itself, the movement only succeeded in obtaining weak statements of support from Libya and Mauritania. As a result of this ambivalence, the movement eventually relocated to Spanish-controlled Western Sahara to start an armed rebellion.