Freiherr Johann Ludwig von Westphalen (11 July 1770 – 3 March 1842) was a liberal government official, Prussian aristocrat with Scottish heritage, and a friend, mentor, and father-in-law of Karl Marx.

Biography

Johann Ludwig von Westphalen was born on 11 July 1770 in Bornum am Elm. He was the youngest son of Christian Philip Heinrich von Westphalen (1724–92), who had been de facto "chief of staff" to Duke Ferdinand of Brunswick during the Seven Years' War, and from whom he inherited the aristocratic title of baron. Through his mother, Jane Wishart of Pittarow, he was the descendent of many Scottish and European noble families.

He received extensive education and spoke German and English, and read Latin, Greek, Italian, French and Spanish. He studied at the Collegium Carolinum, the forerunner of today's Braunschweig University of Technology, and at Göttingen.

In 1794, he entered government's service in Brunswick. 

In 1797 he married Elisabeth von Veltheim, who bore him four children. 

In 1804 he entered the government service of the Duchy of Brunswick and Lunenburg (Wolfenbüttel).

With the establishment of the Napoleonic state in Westphalia (the Kingdom of Westphalia) in 1807, he entered its service. He was likely motivated in this by a desire to see reforms carried out. He did, however, oppose the French dominance of the local government, and other policies, and for his critique he was eventually arrested by orders from Louis-Nicolas Davout and imprisoned in the fortress of Gifhorn. In the same year, he lost his first wife. In the summer of 1809 Louis was appointed sub-prefect of Salzwedel, where three years later in 1812 he married Karoline Heubel; they would have three children. After Salzwedel was again under Prussian administration, in 1816 Ludwig von Westphalen was transferred to the newly established regional government in Trier.

It was in Trier that he met and befriended Heinrich Marx, the father of Karl Marx. 

The children of the respective families, in particular Jenny and Edgar von Westphalen, and Sophie and Karl Marx, became close friends as well. 

In 1836, Jenny von Westphalen and Karl Marx became engaged; at first secretly but Ludwig approved the marriage in 1837, even though some saw Marx, who was both middle class and younger than her, as well as of Jewish descent, as an inappropriate partner for the baronial daughter. In fact, Ludwig was seen as the mentor and role model of Karl Marx, who referred to him as a "dear fatherly friend". It was Ludwig who first introduced Marx to the socialist teachings of Saint-Simon. Marx's dissertation was dedicated to Ludwig. 

In 1842, Marx was present at the deathbed of Ludwig von Westphalen. Jenny and Karl became married in 1843, a year after Ludwig's death.

He was the father of Ferdinand von Westphalen (de), a conservative and reactionary Prussian Minister of the Interior.

He died on 3 March 1842 in Trier.