The Goths occupy a unique place in this story, the only native agriculturists (except, arguably, the Parthians, after they adopted a settled lifestyle) among hordes of nomads.  During the Gothic dominance of the east European plain (2nd through 4th centuries AD), that was the only moment in post-Cimmerian history up to the modern era when the steppe was not in thrall to nomadic empires.  The Goths also spoke a Germanic tongue, which is significant for those who think language is an important criterion in this regard.

The Goths — or at least a ruling elite — originated according to Gothic legend in what is now Sweden.  Certain place names, such as the island of Gotland in the Baltic Sea, appear to recall the Gothic presence.  Encyclopædia Britannica describes those days: ⁷

According to their own legend, reported by the mid-6th-century Gothic historian Jordanes, the Goths originated in southern Scandinavia and crossed in three ships under their king Berig to the southern shore of the Baltic Sea, where they settled after defeating the Vandals and other Germanic peoples in that area.  Tacitus states that the Goths at this time were distinguished by their round shields, their short swords, and their obedience toward their kings.  Jordanes goes on to report that they migrated southward from the Vistula region under Filimer, the fifth king after Berig and, after various adventures, arrived at the Black Sea.

This movement took place in the second half of the 2nd century AD, and it may have been pressure from the Goths that drove other Germanic peoples to exert heavy pressure on the Danubian frontier of the Roman Empire during the reign of Marcus Aurelius.  Throughout the 3rd century Gothic raids on the Roman provinces in Asia Minor and the Balkan peninsula were numerous, and in the reign of Aurelian (270-275) they obliged the Romans to evacuate the trans-Danubian province of Dacia.  Those Goths living between the Danube and the Dniester rivers became known as Visigoths, and those in what is now the Ukraine as Ostrogoths.

Historian William H. McNeill points out that Goths in their new home in what is now the Ukraine “swiftly adopted the habits and accoutrements of steppe nomads.” ⁸  Goths thus became the only mounted warriors among Germans for centuries to come — which Rome learned to her sorrow.

Continuing with the story of the Ostrogothic kingdom in the Ukraine, Britannica notes that: ⁹

Invading southward from the Baltic Sea, the Ostrogoths built up a huge empire stretching from the Don to the Dniester rivers (in present-day Ukraine) and from the Black Sea to the Pripet Marshes (southern Belarus).  The kingdom reached its highest point under King Ermanaric, who is said to have committed suicide at an advanced age when the Huns attacked his people and subjugated them about 370.  Although many Ostrogothic graves have been excavated south and southeast of Kiev, little is known about the empire.  The Ostrogoths were probably literate in the 3rd century, and their trade with the Romans was highly developed.

During the late 4th century the fierce Huns struck from the east, and after a period of successful defense, both Visi- and Ostrogoths were overwhelmed and obliged to accept either Hunish dominance, or escape to the west and south.  Groups of both Visigoths and Ostrogoths eventually made their way into the Roman Empire — more or less with Roman permission — and had various adventures therein.

Visigoths.  In 378 AD the Visigothic cavalry overwhelmed the Roman army near Adrianople, inflicting one of the worst defeats in Roman history.  Under Alaric, in 410 they sacked the city of Rome.  In 418 the Visigoths accepted Roman “federate” status and were settled as nominal allies in the Aquitaine region of southern Gaul, and though they remained officially bound to Rome for many years, over the rest of the century from this nucleus they built a mighty kingdom incorporating much of what is now France and most of modern Spain and Portugal.

As a result of the battle of Vouillé (507), the Visigoths were expelled from Gaul (except for the small Mediterranean coastal strip of Septimania) by the Franks under Clovis.  Excepting Septimania, the Visigoths withdrew behind the Pyrenees mountains into their Spanish dominions, and remained there, their kingdom slowly percolating along, not very prosperously, until they were overwhelmed by the Arab Muslim irruption across the strait at Gibraltar in 711.  The Goths of Septimania, at first passing with the rest of the Visigothic realm to the Muslims of Spain, eventually transferred their allegiance to the Franks, and the region was afterward known for centuries in France as “Gothia.”

From refuges in the northern mountains of Spain, under frequent attack from the Muslim Caliphate centered in Cordova to the south, over more than a half millennium of time the Visigothic kingdom's heirs slowly returned, in the Spanish-Portuguese Reconquista (see Impearls' article Crusades I [permalink]).

Ostrogoths.  The Ostrogothic story was different.  The Ostrogoths, after first being settled by the East Roman Empire in what used to be called Yugoslavia, towards the end of the 5th century were induced by the East Roman Emperor to invade Italy, ruled by the barbarian king Odoacer, who had lately put an end to the remains of the Roman Empire in the West.  The Ostrogoths, under their king Theodoric the Great, defeated Odoacer, and in 493 Theodoric became king of the Ostrogothic kingdom of Italy.  For most of the next half century Ostrogothic Italy remained relatively prosperous and enlightened amid the darkness taking hold elsewhere.  Roman civilization had not yet winked out in Italy; literary works continued to be written in Latin, and Theodoric maintained a benevolent rule over both Italians and Ostrogoths.

This state of affairs, after the death of Theodoric, was brought to an end by the Eastern Emperor Justinian, who in 535 launched an invasion of Ostrogothic Italy in order to retrieve it for the Roman Empire, commanded by the brilliant general Belisarius, who had just lately reconquered Vandal Africa for the Byzantine domain.  Justinian, however, was paranoid and suspicious of Belisarius, and failed to provide him with enough troops, whereupon the war dragged on literally for decades, devastating most of Italy and doing much to propel it into the Dark Ages.  Belisarius was recalled, his successors proved incompetent; Belisarius was sent back, but still not given adequate backing; finally, another general, the eunuch Narses, was installed in command, with a massive army properly supported this time, and the war, finally in 554, was won.  Devastated Italy — Rome itself — were indeed recovered for the Roman Empire; that is, until the far more barbaric Lombards invaded a few years later, completing the demolition job on classical Italy.  The Ostrogoths of Italy were not heard of again.

Gothic continued to be spoken for centuries, however, by peasants in the Danube valley, while a small enclave of Ostrogoths, separated from the main movements of their people, retained its identity in the Crimea (modern Ukraine) throughout the medieval period.

Assessment:  The Goths, Ostro- and Visi-, one would have to say, are among the strongest candidates for a close resemblance to the Rohirrim.  Agriculturalists, and Germanic speakers, these are additional factors in their favor for those who value such things.  After picking up numerous nomads, Sarmatians among them, into their confederacy, they became fine horse warriors, dominating the east European steppe for a couple of hundred years.  Furthermore, the Goths came from “the north,” and after conquering Roman Dacia (modern Romania), they certainly occupied “lands that had once been part of the domain of a neighboring culture that is both older and more highly developed.”  Ater occupying much of formerly-Roman Gaul, Spain, and Italy, this was even more true.  Goths, one must conclude, are fine candidate folk to be the Rohirrim.