[3] During his 1850 visit to New Orleans, Löwenthal played Paul Morphy on two separate occasions, losing a total of three games straight.

"...I am convinced that I was vanquished by superior strength," Löwenthal said about the match, as reported by an English writer named Frederick Edge, who wrote extensively about Morphy and other famous players in a book called The Exploits and Triumphs, in Europe, of Paul Morphy, the Chess Champion.

No doubt aware that chess was Löwenthal's only source of livelihood, and conscious to not be considered a professional player himself, Morphy, after winning the match stakes of £100, presented Löwenthal with a gift of furniture valued at £120 for his new house.

Just days after being defeated by Morphy, Löwenthal had his greatest success by winning the British Chess Association Congress knockout tournament in Birmingham, England, on 27 August 1858.

Löwenthal was for some time chess editor of The Illustrated News of the World and of The Era.