'proinsurrectionally' originates from Latin elements: the prefix 'pro-' (from Latin 'pro', meaning 'for' or 'in favor of') combined with 'insurrection' (from Latin 'insurrectio'/'insurrect-'), plus the adjective-forming suffix '-al' and the adverbial suffix '-ly'.

'insurrection' entered English via Old French/Medieval Latin from Latin 'insurrectio' (from 'insurgere', 'in-' + 'surgere' meaning 'to rise up'); 'pro-' is a Latin prefix meaning 'for'; the adjective 'proinsurrectional' is formed by adding '-al', and the adverb 'proinsurrectionally' by adding '-ly'.

Originally the Latin root 'insurgere' and related forms meant 'to rise up'; over time English 'insurrection' has kept the sense of a violent uprising, and 'pro-' appended to it has come to mark support for that uprising; thus the combined form denotes support for revolt.