During much of its history, and especially during the Francoist dictatorship (1939–1975), the Catalan language has often been degraded as a mere <answer>dialect of Spanish</answer>. This view, based on political and ideological considerations, has no linguistic validity. Spanish and Catalan have important differences in their sound systems, lexicon, and grammatical features, placing the language in a number of respects closer to Occitan (and French). 
What has Catalan often been considered?
dialect of Spanish