Cambyses II in the context of "Cassandane"

Cyrus II of Persia (c. 600 – 530 BC), commonly known as Cyrus the Great, was the founder of the Achaemenid Empire. Hailing from Persis, he brought the Achaemenid dynasty to power by defeating the Median Empire and embracing all of the previous civilized states of the ancient Near East, expanding vastly across most of West Asia and much of Central Asia to create what would soon become the largest empire in history at the time. The Achaemenid Empire's greatest territorial extent was achieved under Darius the Great, whose rule stretched from Southeast Europe in the west to the Indus Valley in the east.

After absorbing the Median Empire, Cyrus conquered Lydia and eventually the Neo-Babylonian Empire, granting him control of Anatolia and the Fertile Crescent, respectively. He also led a major expedition into Central Asia, where his army brought "into subjection every nation without exception" before he allegedly died in battle with the Massagetae, a nomadic Eastern Iranian people, along the Syr Darya in December 530 BC. However, according to Xenophon of Athens, Cyrus did not die fighting and had instead returned to the capital city of Pasargadae. Regardless of the date of his death, he was succeeded by his son Cambyses II, whose campaigns into North Africa led to the conquests of Egypt, Nubia, and Cyrenaica during his short rule.

The Late Period of ancient Egypt refers to the last flowering of native Egyptian rulers after the Third Intermediate Period in the 26th Saite Dynasty founded by Psamtik I, but includes the time of Achaemenid rule over Egypt after the conquest by Cambyses II in 525 BC as well. The Late Period existed from 664 BC until 332 BC, following a period of foreign rule by the Nubian 25th Dynasty and beginning with a short period of Neo-Assyrian suzerainty, with Psamtik I initially ruling as their vassal. The period ended with the conquests of the Achaemenid Empire by Alexander the Great and establishment of the Ptolemaic dynasty by his general Ptolemy I Soter, one of the Hellenistic diadochi from Macedon in northern Greece. With the Macedonian Greek conquest in the latter half of the 4th century BC, the age of Hellenistic Egypt began.

Meroë (/ˈmɛroʊiː/; also spelled Meroe; Meroitic: 𐦨𐦡𐦷𐦡𐦥𐦢, romanized: Medewi; Arabic: مرواه, romanized: Meruwah and مروي, Meruwi; Ancient Greek: Μερόη, romanized: Meróē) was an ancient city on the east bank of the Nile about 6 km north-east of the Kabushiya station near Shendi, Sudan, approximately 200 km north-east of Khartoum. Near the site is a group of villages called Bagrawiyah (Arabic: البجراوية). This city was the capital of the Kingdom of Kush for several centuries from around 590 BC, until its collapse in the 4th century AD. The Kushitic Kingdom of Meroë gave its name to the "Island of Meroë", which was the modern region of Butana, a region bounded by the Nile (from the Atbarah River to Khartoum), the Atbarah and the Blue Nile.

The city of Meroë was on the edge of Butana. There were two other Meroitic cities in Butana: Musawwarat es-Sufra and Naqa. The first of these sites was given the name Meroë by the Persian king Cambyses, in honor of his sister who was called by that name. The city had originally borne the ancient appellation Saba, named after the country's original founder. The eponym Saba, or Seba, is named for one of the sons of Cush (see Genesis 10:7). The presence of numerous Meroitic sites within the western Butana region and on the border of Butana proper is significant to the settlement of the core of the developed region. The orientation of these settlements exhibit the exercise of state power over subsistence production.

The Twenty-seventh Dynasty of Egypt (notated Dynasty XXVII, alternatively 27th Dynasty or Dynasty 27), also known as the First Egyptian Satrapy (Old Persian: 𐎸𐎭𐎼𐎠𐎹, romanized: Mudrāya), was a satrapy of the Achaemenid Empire between 525 and 404 BC. It was founded by Cambyses II, the King of Persia, after the Battle of Pelusium (525 BC) and the Achaemenid conquest of Egypt, and his subsequent crowning as Pharaoh of Egypt. It was disestablished upon the rebellion and crowning of Amyrtaeus as Pharaoh. A second period of Achaemenid rule in Egypt occurred under the Thirty-first Dynasty of Egypt (343–332 BC).

Bardiya or Smerdis (Old Persian: 𐎲𐎼𐎮𐎡𐎹 Bardiya; Ancient Greek: Σμέρδις Smérdis; possibly died 522 BCE), also named as Tanyoxarces (Old Persian: *Tanūvazraka; Ancient Greek: Τανυοξάρκης Tanuoxárkēs) by Ctesias, was a son of Cyrus the Great and the younger brother of Cambyses II, both Persian kings. There are sharply divided views on his life. Bardiya either ruled the Achaemenid Empire for a few months in 522 BCE, or was impersonated by a magus called Gaumata (Old Persian: 𐎥𐎢𐎶𐎠𐎫 Gaumāta), whose name is given by Ctesias as Sphendadates (Old Persian: *Spantadātah; Ancient Greek: Σφενδαδάτης Sphendadátēs), until he was toppled by Darius the Great.

The Behistun Inscription (also Bisotun, Bisitun or Bisutun; Persian: بیستون, Old Persian: Bagastana, meaning "the place of god") is a multilingual Achaemenid royal inscription and large rock relief on a cliff at Mount Behistun in the Kermanshah Province of Iran, near the city of Kermanshah in western Iran, established by Darius the Great (r. 522–486 BC). It was important to the decipherment of cuneiform, as it is the longest known trilingual cuneiform inscription, written in Old Persian, Elamite, and Babylonian (a variety of Akkadian).

Authored by Darius the Great sometime between his coronation as king of the Persian Empire in the summer of 522 BC and his death in autumn of 486 BC, the inscription begins with a brief autobiography of Darius, including his ancestry and lineage. Later in the inscription, Darius provides a lengthy sequence of events following the death of Cambyses II in which he fought nineteen battles in a period of one year (ending in December 521 BC) to put down multiple rebellions throughout the Persian Empire. The inscription states in detail that the rebellions were orchestrated by several impostors and their co-conspirators in various cities throughout the empire, each of whom falsely proclaimed himself king during the upheaval following Cambyses II's death. Darius the Great proclaimed himself victorious in all battles during the period of upheaval, attributing his success to the "grace of Ahura Mazda".

The first Achaemenid conquest of Egypt took place in 525 BCE, leading to the foundation of the Twenty-seventh Dynasty of Egypt, also known as the "First Egyptian Satrapy" (Old Persian: Mudrāya). Egypt thus became a satrapy of the Achaemenid Empire until 404 while still maintaining Egyptian royalty customs and positions. The conquest was led by Cambyses II, who defeated the Egyptians at the Battle of Pelusium (525 BCE), and crowned himself pharaoh. Achaemenid rule was disestablished upon the rebellion and crowning of Amyrtaeus as Pharaoh. A second period of Achaemenid rule in Egypt occurred under the Thirty-first Dynasty of Egypt (343–332 BCE).