To lump liberial republicans of 19 th century europe as left in the spectrum of political theory is preposterous.
They were the vanguard of the “bourgeois-democratic” revolutions (such as in 1830 and 1848), fighting to dismantle the “old scaffolding of wrong”—the absolute monarchies and feudal privileges of the Concert of Europe (Conservatism - 19th Century, Ideology, Burke | Britannica)
As a distinct working class (proletariat) emerged, liberal republicans became more afraid of social revolution from below than of the old monarchies from above. This fear led them to compromise with conservative forces to maintain social order and protect private property. This moment in “liberalism” began its transformation into a tool for preserving the capitalist system rather than overthrowing tyranny