Den, also known as Hor-Den, Dewen, and Udimu, was the Horus name of a pharaoh of the Early Dynastic Period who ruled during the First Dynasty of Egypt.

Den was the first to use the title "King of Upper and Lower Egypt" and the first depicted as wearing the double crown (red and white).

Notably, the floor of his tomb at Umm El Qa'ab, near Abydos, was constructed using red and black granite, making it the earliest known use of this hard stone as a building material in Egypt with a flight of stairs leading to it.

During his long reign, he established many of the customs of court ritual and royalty drawn on by later rulers and was held in high regard by his immediate successors.

[4] Den's serekh name is well attested on earthen seal impressions, on ivory labels and in inscriptions on vessels made of schist, diorite and marble.

Subsidiary tombs and palatial mastabas at Sakkara belonged to high officials such as Ipka, Ankh-ka, Hemaka, Nebitka, Amka, Iny-ka and Ka-Za.

From Den's reign onwards, the Egyptians used numbering hieroglyphs for a range of purposes including calculating tax collections and for annotating their year events.

[13] Most religious and political happenings from Den's reign are recorded in the numerous ivory tags and the Palermo Stone inscription.

A nearby inscription begins with “Henu...” but it is unclear, if that means “provision” or if it is the first syllable of the name “Henu-Ka” (a high official).

Plundering nomads, known by the early Egyptians as jwntj.w "people with hunting bows”, were regular foes of Egypt, often causing trouble.

It is possible the tomb was used as a storehouse for surplus produce during the king's lifetime, while also making it easier to add grave goods for later use in the afterlife by Den.

Twenty labels made of ivory and ebony were found in his tomb, 18 by Flinders Petrie in the spoil heaps left by the less thorough Émile Amélineau.

[23] Among these labels are the earliest known depictions of a pharaoh wearing the double-crown of Egypt (see above), as well as running between ritual stele as part of the Sed festival.

Thought to be the king's retainers, an examination of some of the skeletons suggests they were strangled, making this an example of human sacrifice which is considered to be common with the pharaohs of the First Dynasty.

This practice seems to have ceased by the end of the dynasty, with ushabtis taking the place of the bodies of actual people to aid the pharaohs with the work expected of them in the afterlife.