Ahmose I - Nebpehtyre
Ahmose I was the first pharaoh of the 18th dynasty. He was a descendant of the 17th dynasty which was based in Thebes in Upper Egypt. His father Seqenenre and his brother Kahmose were the last 2 pharaohs of the 17th dynasty. His family, originating from Thebes, lead a rebellion against the Hyksos (Amalekites) who were foreign invaders who had controlled Lower Egypt for some 400yrs following the Exodus of the Israelites which left Egypt crippled. (This was Egypt's second intermediate period; otherwise known as dynasties 15 to 17). The 17th dynasty in Upper Egypt was contemporary with the Hyksos (15th dynasty) in Lower Egypt. Ahmose I's father Seqenenre and his brother Kahmose (pharaohs of the 17th dynasty) were killed fighting the Hyksos. The Hyksos (Amalekites) were finally defeated with the help of King Saul and David of Israel. Ahmose I began the 18th dynasty at a very young age and was co-regent with his mother Queen Aahotep initially.  The 18th dynasty was actually a continuation of the 17th dynasty, but was expanded to include Lower Egypt as the Hyksos had been forced to leave. The ancient historian Manetho decided to make this a new dynasty even though it was the same family line as the 17th dynasty. Ahmose I reigned from Thebes for 25 years and 4 months. The Revised Dates of his reign: 1021BC - 996BC approximately 
The Second Intermediate Period
Main Article: Hyksos
Egypt was destabilised when Moses (Amenemhet IV) went into exile as there was nobody to continue the 12th dynasty. When Amenemhet III died, his daughter Sobeknefru had to become pharaoh. She only lived for 4 years (possibly 8 years) and when she died, the 12th dynasty ended.
Egypt suffered massive losses 40 years later under Neferhotep as a result of the Exodus (1446BC). This brought about the end of the 13th dynasty. Egypt became vulnerable to invasion as a result of plagues and the loss of it's leader, it's army, it's slaves and it's chariots.
As the Israelites were leaving Egypt, they met up with the Hyksos (Amalekites) as they were leaving. The Amalekites attacked them but Joshua and his men prevailed as Moses held his arms up for the men to see on top of a hill. The Amalekites passed by but Moses prophesied that they would always be at war with Israel until their final destruction. Exodus 17:8-16 Numbers 24:20
The Hyksos took over and ruled Lower Egypt for the next 400 yrs (the second intermediate period). The Hyksos were 'foreigners' to Egypt and are thought to have originated in Arabia. The word 'Hyksos' meant 'Foreigner' but in Eastern dialects where the Hyksos originated, it meant 'Shepherd Kings'. They were able to take over Lower Egypt with very little resistance. 
The 17th dynasty was contemporay with the Hyksos (15th dynasty); but in a different part of the country (Upper Egypt).
Saul attacked Amalekites / Hyksos as instructed by Samuel the last Judge of Israel. He defeated them all the way from Havilah to Shur, near the eastern border of Egypt, not sparing any. Saul did, however, captured the Hyksos (Amalekite) king alive (his name was Agag) and he kept their cattle as plunder. Agag was brought to Samuel who put him to death. Samuel was not happy with Saul for not following his instructions fully. 1Samuel 15:1-34
Later, at a time when David was fleeing from Saul, when he was living in Philistine territory, he raided the Geshurites, the Girzites and the Amalekites. From ancient times these peoples had lived in the land extending to Shur and Egypt. Whenever David attacked an area, he did not leave a man or woman alive, but took sheep and cattle, donkeys and camels, and clothes. 1Samuel 27:1-12
Once David's camp was raided by some Amalekites (Hyksos) and his wives, sons and daughters were taken captive. David and most of his band of 400 men pursued the Amalekites and recovered all that was stolen and completely destroyed the Amalekites taking their herds as plunder. 1Samuel 30:1-31
Egypt's New Kingdom
The Hyksos were eventually defeated in an uprising lead by the family of Ahmose I from Upper Egypt. Ahmose I lost his father Seqenenre and his brother Kahmose fighting the Hyksos. The Hyksos were forced to leave Egypt and Ahmose I (Nebpehtyre) became the first pharaoh of the 18th dynasty (which was the beginning of New Kingdom of Egypt as it is known). Ahmose I became the pharaoh at a very young age and was coregent with his mother Queen Aahotep in the early part of his reign. He reigned for 25 years and was a contemporary of Saul and David.  The Theban 17th dynasty situated in Upper Egypt was actually contemporary with the Hyksos (15th dynasty) situated in Lower Egypt. The 18th dynasty was realy a continuation of the 17th dynasty but the boundaries had expanded to include Lower Egypt. Ahmose I was the son of Seqenenre and the brother of Kahmose who were the last two pharaohs of the 17th dynasty. As the Hyksos had been defeated and forced to leave Egypt, the ancient historian Manetho decided to make this a new dynasty.
- Peter A Clayton Chronicle of the Pharaohs The Reign by reign record of the rulers and dynasties of Ancient Egypt. Thames and Hudson 2006 ISBN 978-0-500-28628-9
- Unwrapping the Pharaohs How Egyptian Archaeology confirms the Biblical Timeline. John Ashton & David Down. Master Books 2006. ISBN 978-0-89051-468-9 ISBN 0-89051-468-2
- The Hyksos identified Terry Hurlbut http://www.examiner.com/article/the-hyksos-identified
- Who were the Hyksos? Save-Soderbergh, t. (1951) The Hyksos rule in Egypt, The Journal of Egyptian Archaeology, Egypt Exploration Society.