Who was the wealthiest man in the world in the 1830s?

Wu Bingjian, better known in the west as ‘Houqua’, or sometimes ‘Howqua’, was the most successful Chinese merchant of his day.  As leader of the Cohong (gonghang), the guild of Chinese traders that had been authorized in the late 18th century by the Qing court to oversee trade with Western merchants at Canton (Guangzhou), he was at once the richest man in the world.  In 1834, Wu’s personal wealth was estimated at 26 million Mexican silver dollars (£6.24 million then, around (£680 million today).  To put this wealth in perspective, the contemporary European financier Nathan Rotschild held capital equivalent to US $5.3 million (around £1.06 million) in 1828.  Wu’s extraordinary ability to maintain a complex balance between his business interests, the Qing court and his Western partners, made him the most importnat player in Western countries’ trade with China for over half a century.

That is from the new and quite interesting Creators of Modern China: 100 Lives from Empire to Republic 1796-1912, edited by Jessican Harrison-Hall and Julia Lovell.