Question: What was the nationality of Marcus Goldman's son-in-law?

Context paragraphs:
Marcus Goldman: Marcus Goldman ( ; December 9, 1821 – July 20, 1904) was a German banker, businessman, and financier.  He was born in Trappstadt, Bavaria and immigrated to the United States in 1848.  He was the founder of Goldman Sachs, which has since become one of the world's largest investment banks.

Battle of Carnuntum: The Battle of Carnuntum took place in 170 A.D. during the Marcomannic Wars.  In the spring of 170 A.D. swarms of German warrior bands attacked Roman provinces along the Danube River.  In furtherance of this endeavor, and for mutual protection, the king of the Marcomanni, Ballomar, had formed an alliance with the Quadi tribe.  Roman Emperor Marcus Aurelius with his son-in-law and chief military adviser Tiberius Claudius Pompeianus crossed the Danube River to drive back the raiders.  The Romans and Germans met outside Carnuntum in Upper Pannonia, which was the headquarters for the 14th Legion.  The Roman army was inexperienced and outmatched, and the ensuing battle was a disaster for the Romans.  Although the legions fought hard and bravely, they were no match for the Germanic warriors.  20,000 Romans were killed.  Following this victory the Germans besieged Aquileia and sacked Opitergium.  Carnuntum was the worst Roman defeat in a century.

Marcus Vipsanius Agrippa: Marcus Vipsanius Agrippa ( ; 64/62 BC – 12 BC) was a Roman consul, statesman, general and architect.  He was a close friend, son-in-law, and lieutenant to Octavian and was responsible for the construction of some of the most notable buildings in the history of Rome and for important military victories, most notably at the Battle of Actium in 31 BC against the forces of Mark Antony and Cleopatra.  As a result of these victories Octavian became the first Roman Emperor, adopting the name of Augustus.  Agrippa assisted Augustus in making Rome a city of marble and renovating aqueducts to give all Romans, from every social class, access to the highest quality public services.  He was responsible for the creation of many baths, porticoes and gardens, as well as the original Pantheon.  Agrippa was also father-in-law to the second Emperor Tiberius, maternal grandfather to Caligula, and maternal great-grandfather to the Emperor Nero.

Gaius Aufidius Victorinus: Gaius Aufidius Victorinus was a Roman senator and general of the second century.  A friend of the Emperor Marcus Aurelius and the son-in-law of the advocate and orator Marcus Cornelius Fronto, he was twice consul and governor of several Roman provinces.

James S. Marcus: James Stewart Marcus (15 December 1929 – 5 July 2015) was an American philanthropist and investment banker at Goldman Sachs who supported classical music, opera and the vocal arts in and around New York City.  He served as Chairman of the Board of Directors of the Metropolitan Opera for eight years.

Do Nothing till You Hear from Me (radio program): Do Nothing till You Hear From Me (2004) was a six-part BBC Radio 4 sitcom written by British comic actor and writer Marcus Powell based on his Roy Diamond character.  In the radio version, produced by Carole Smith, the cantankerous Jamaican stand-up comedian played by Powell was transformed into an equally cantankerous trombone player, Roy Walcott, played by Ram John Holder (of "Desmond's" and "Porkpie" fame).  The stellar supporting cast included Sam Kelly (Porridge) George Layton, Yvonne Brewster, Caroline Lee Johnson ("Chef! ") and Marcus himself playing Roy's long-suffering son-in-law Victor.

Goldman–Sachs family: The Goldman–Sachs family is a family of German Jewish descent known for the leading investment bank Goldman Sachs.  Marcus Goldman's youngest daughter, Louisa, married Samuel Sachs, the son of close friends and fellow Lower Franconia, Bavaria immigrants.  Louisa's older sister and Sam's older brother had already married.  His oldest son, Julius Goldman, married Sarah Adler, daughter of Samuel Adler.  In 1882, Goldman invited his son-in-law Samuel to join him in the business and changed the firm's name to "M. Goldman and Sachs".  For almost fifty years, all the partners came from the extended family.

Marcus J. Goldman: Marcus Jacob Goldman, MD (born November 27, 1960), is a physician, board certified in psychiatry with past certifications in addiction, forensic and geriatric psychiatry and is also a writer.  Dr. Goldman is an associate professor at Tufts University School of Medicine, where he has served on the admissions’ committee and has had past academic and teaching appointments at Harvard Medical School and the University of Massachusetts Medical School.

Samuel Sachs: Samuel Sachs ( ; July 28, 1851 – March 2, 1935) was an American investment banker.

Maxentius: Maxentius (Latin: "Marcus Aurelius Valerius Maxentius Augustus" ; c. 278 – 28 October 312) was Roman Emperor from 306 to 312.  He was the son of former Emperor Maximian and the son-in-law of Emperor Galerius.  The latter part of his reign was preoccupied with civil war, allying with Maximinus II against Licinius and Constantine.  The latter defeated him at the Battle of the Milvian Bridge in 312, where Maxentius, with his army in flight, is supposed to have perished by drowning in the Tiber River.

Supporting paragraphs: Goldman–Sachs family Samuel Sachs
Answer: American