[5][6] This also gave new impetus to the republican "states party", which had been weakened since the murder of Johan van Oldenbarnevelt, and was able to determine Amsterdam politics up to the crisis of the Rampjaar in 1672.

The proponents of the De Graeff family has shown they had an eye for national politics and tried to find some balance between the House of Orange and the Republicans.

Together with the Republican-minded brothers and their cousins Andries, Cornelis and Jan Bicker, the family De Graeff strived for the abolition of stadtholdership.

The couple had six children reaching adulthood:[10][11] On September 18, 1610, Jacob Dircksz de Graeff acquired the High Lordship of Zuid-Polsbroek from Charles of Aremberg,[12] which was freely inheritable and sellable as an allod.

[13] Their acquisition increased the reputation and contributed to the aristocratization of the family, in which De Graeff and his heirs could be addressed as Vrijheer(en) van Zuid-Polsbroek ever since.

In 1591 he undertook a grand tour of France, Italy and Germany with his friend Justus Lipsius and then lived in Geneva for three years in the house of the Calvinist preacher Giovanni Diodati.

[16] He was friends with burgomaster Cornelis Hooft, and competed with him on a committee on the city of Amsterdam's expansion plans against "self-seeking" land speculators Frans Hendricksz Oetgens van Waveren and Bartholt Cromhout.

[17] At this time, a powerful Calvinist faction under Reynier Pauw crystallized in the Vroedschap, to which De Graeff and his ally Hooft kept their distance, and thus diminished their own influence.

This attitude brought him politically to the side of the state advocate Van Oldenbarnevelt[9] and Hugo Grotius, whose socio-political position he prolonged as the local representative of Amsterdam.

The Counter-Remonstrants (enemies of the Remonstrants) opposed this, and the stadtholder, Maurice of Nassau viewed this policy as a challenge to his authority as commander-in-chief of the States Army.

De Graeff was therefore expelled from the government after Oldenbarnevelt's disempowerment and his subsequent beheading in 1618, on the initiative of the stadholder Maurits of Orange and the Amsterdam regent Reynier Pauw.

[19] In the field of science and natural history, De Graeff and Hooft maintained a close collaboration with Constantijn Huygens and via him also with René Descartes.

[14] After the death of Maurits of Oranje[16] in 1625 and the political collapse of the orangist Reynier Pauw in 1627 Jacob Dircksz de Graeff returned to power again.

[9] During this time, De Graeff was repeatedly offered the post of Gecommitteerde Rad der Holland und West-Friesland in The Hague, which he never accepted.

The poet and writer Joost van den Vondel wrote an obituary for him with "De titel maakt alleen geen Graef".