Margaret L. Anderson argues that he was "Imperial Germany's greatest parliamentarian" and bears comparison with Irishmen Daniel O'Connell and Charles Stewart Parnell "in his handling of party machinery and his relation to the masses.

When Prussia absorbed Hanover and then set up the German Empire in 1871, Windthorst dealt with the new state of affairs and became a leader of the all-Catholic Centre Party.

Windthorst was born at Kaldenhof manor in the present-day municipality of Ostercappeln, in the lands of the former Prince-Bishopric of Osnabrück, which had been secularised to the Electorate of Hanover under the Protestant Welf dynasty in 1803.

He was educated at the Gymnasium Carolinum, an endowed school at Osnabrück which he left with excellent Abitur exams, and from 1830 studied law at the universities of Göttingen and Heidelberg.

The March Revolution opened for him—as for so many of his contemporaries—the way to public life and though he failed to gain a mandate for the Frankfurt Assembly, he was elected representative for his native district in the second chamber of the reformed Hanoverian parliament in 1849.

Windthorst took no part in the critical Austro-Prussian War; contrary to the opinion of many of his friends, after the annexation of Hanover by Prussia, he accepted the fait accompli, took the oath of allegiance, and was elected a member both of the Prussian parliament and of the North German diet.

He acted as representative of his exiled king in the negotiations with the Prussian government concerning his private property, and opposed the sequestration, and for the first time was placed in a position of hostility to Otto von Bismarck.

It was chiefly owing to his skill and courage as a parliamentary debater and his tact as a leader, that the party held its own and constantly increased in numbers during the great struggle with the Prussian government.

His relations with the emperor William II became very cordial, and in 1891 he achieved a great parliamentary triumph by defeating the School bill and compelling Gossler to resign.

[citation needed] His funeral was a most remarkable display of public esteem, in which nearly all the ruling princes of Germany joined, and was a striking sign of the position to which, after twenty years of incessant struggle, he had raised his party.

[2] According to historian Golo Mann, Windthorst was one of the greatest of German parliamentary leaders: no one equaled him in his readiness as a debater—his defective eyesight compelling him to depend entirely upon his memory.