7th century

The 7th century is the period from 601 to 700 in accordance with the Julian calendar in the Common Era. The Muslim conquests began with the unification of Arabia by Muhammad starting in 622. After Muhammad's death in 632, Islam expanded beyond the Arabian Peninsula under the Rashidun Caliphate (632–661) and the Umayyad Caliphate (661–750). The Islamic conquest of Persia in the 7th century led to the downfall of the Sassanid Empire. Also conquered during the 7th century were Syria, Palestine, Armenia, Egypt, and North Africa.

The Byzantine Empire continued suffering setbacks during the rapid expansion of the Arab Empire.

In the Iberian Peninsula, the 7th century was the Siglo de Concilios, that is, century of councils, referring to the Councils of Toledo.

Harsha united Northern India, which had reverted to small republics and states after the fall of the Gupta Empire in the 6th century.

In China, the Sui dynasty was replaced by the Tang dynasty, which set up its military bases from Korea to Central Asia, and was next to the Arabian later. China began to reach its height. Silla allied itself with the Tang Dynasty, subjugating Baekje and defeating Goguryeo to unite the Korean Peninsula under one ruler. The Asuka period persisted in Japan throughout the 7th century.

Century

A century (from the Latin centum, meaning one hundred; abbreviated c.) is 100 years. Centuries are numbered ordinally in English and many other languages (e.g. "the 7th century AD/CE"). A centenary is a hundredth anniversary or a celebration of this, typically remembrance of an event which took place a hundred years earlier; and its adjectival form is centennial.

Start and end in the Gregorian Calendar

According to the Gregorian calendar, the 1st century AD/CE started on January 1, 1, and ended on December 31, 100. The 2nd century started at year 101, the 3rd at 201, etc. The n-th century started/will start on the year (100 × n) − 99 and ends in 100 × n. A century will only include one year, the centennial year, that starts with the century's number (e.g. 1900 is the final year in the 19th century).

1st century BCE and AD

There is no "zeroth century" in between the 1st century BCE and the 1st century AD. Also, there is no year 0 AD. The Julian calendar "jumps" from 1 BCE to 1 AD. The first century BCE includes the years 100 BCE to 1 BCE. Other centuries BCE follow the same pattern.