AD 1000 in the context of "Common year starting on Wednesday"

The first millennium of the anno Domini or Common Era was a millennium spanning the years 1 to 1000 (1st to 10th centuries; in astronomy: JD 1721425.5 – 2086667.5). The world population rose more slowly than during the preceding millennium, from about 200 million in the year 1 to about 300 million in the year 1000.

In Western Eurasia (Europe and Near East), the first millennium was a time of great transition from Classical Antiquity to the Middle Ages. The 1st century saw the peak of the Roman Empire, followed by its gradual decline during the period of Late Antiquity, the rise of Christianity and the Great Migrations. The second half of the millennium is characterized as the Early Middle Ages in Europe, and marked by the Viking expansion in the west, and the continuation of the Byzantine Empire (Eastern Roman Empire) in the east.

Old Saxony was the homeland of the Saxons who fought the Frankish empire during the Early Middle Ages, until they conquered it and converted it into a Carolingian stem duchy in the 8th century, the Duchy of Saxony. Contemporary authors such as Bede and the author of the Ravenna Cosmography used the term "Old Saxons" to distinguish them from the Saxons living in Britain, also known as Anglo-Saxons, who they believed had migrated from Old Saxony. Roman sources as far back as the fourth century had described these continental Saxons as northern neighbours of the Franks, who lived near the Lower Rhine. They do not appear to have been politically unified, although they sometimes worked together to fight the Franks. Bede described them as ruled by "satraps".

Old Saxony, like the later duchy of Saxony, included the inland regions later known as Eastphalia, Westphalia and Angria (or Angaria), between the Rhine and Elbe rivers. They possibly also already lived in Nordalbingia, north of the mouth of the Elbe. There is a single uncertain report of a smaller Saxon tribe living in this region in the second century, and this may represent the origin of their name. During their wars with the Frankish empire, the Saxons were described as living north of the Thuringians, as far east as the Elbe. By the time of the Carolingians, most of the North Sea coast between the Rhine and Elbe was inhabited not by the Saxons, but by the medieval Frisians, who were seen as distinct from the Saxons.

The history of the Jews in Alsace is one of the oldest in Europe. It was first attested to in 1165 by Benjamin of Tudela, who wrote about a "large number of learned men" in "Astransbourg"; and it is assumed that it dates back to around the year 1000. Although Jewish life in Alsace was often disrupted by outbreaks of pogroms, at least during the Middle Ages, and reined in by harsh restrictions on business and movement, it has had a continuous existence ever since it was first recorded. At its peak, in 1870, the Jewish community of Alsace numbered 35,000 people.

The 10th century was the period from 901 (represented by the Roman numerals CMI) through 1000 (M) in accordance with the Julian calendar, and the last century of the 1st millennium.

In China, the Song dynasty was established, with most of China reuniting after the fall of the Tang dynasty and the following Five Dynasties and Ten Kingdoms period. The Muslim World experienced a cultural zenith, especially in al-Andalus under the Caliphate of Córdoba and in the Samanid Empire under Ismail Samani. The Abbasid Caliphate continued to exist but with reduced central authority. Additionally, there was a cultural flourishing for the Byzantine Empire, which also reconquered some lost territories, and the First Bulgarian Empire, as well as the Holy Roman Empire during the Ottonian Renaissance. The historian Lynn White mentions of the period that "to the modern eye, it is very nearly the darkest of the Dark Ages ... if it was dark, it was the darkness of the womb". Caesar Baronius described it as the Iron Century, because it was 'iron in its harshness and in its sterility of goodness', while Lorenzo Valla gave it the similar name "Age of Lead and Iron".

Gau (German: [ɡaʊ] ; Dutch: gouw [ɣʌu] ; West Frisian: gea [ɡɪə] or goa [ɡoə]) is a Germanic term for a region within a country, often a former or current province. It was used in the Middle Ages, when it can be seen as roughly corresponding to an English shire. The administrative use of the term was revived as a subdivision during the period of Nazi Germany in 1933–1945. It still appears today in regional names, such as the Rheingau or Allgäu.