He was born in Sagard on the island of Rügen, the son of the pastor Philipp Philipp von Willich [de] (1720–1787) and half-brother of the country doctor Moritz von Willich [de] (1750–1810), the first country physician in Swedish Pomerania.
[2] At first Willich was the tutor and business-partner of Wilhelm Graf von Schwerin-Putzar in Prenzlau.
From the spring of 1803 he was a chaplain in the Queen's Regiment in Stralsund, which at that time belonged to Swedish Pomerania.
She was daughter of the royal Prussian lieutenant-colonel Friedrich Gottlieb von Mühlenfels[4] († 1801), a Squire on Sissow (today part of Gustow, island of Rügen), and of Pauline of Campagne.
Almost two months before the birth of his eponymous son, while Napoleon's troops were besieging Stralsund (see Coalition Wars), Willich died of nerve fever (typhus), which at that time was rampant in the city.