[4][5] According to the 5th century historian Sozomen, whose family had lived in the town for several generations, the townspeople started converting to Christianity due to the hermit Hilarion who is attributed to have healed miraculously a citizen called Alaphion.

[8] A marble slab, deposited in the maqam of Salim Abu Musallam in Beit Lahia is inscribed in late Mamluk naskhi letters.

It had a population of 70 Muslim households and paid a fixed tax rate of 25% on various agricultural products, including wheat, barley, summer crops, vineyards, fruit trees, goats and/or beehives.

[10] During the 17th and 18th centuries, the area of Beit Lahia experienced a significant process of settlement decline due to Bedouin pressures on local communities.

He described it: [P]eopled by 250 inhabitants, it occupies an oblong valley, well cultivated, and surrounded by high sand-dunes, which cause a great heat.

It is a little oasis, incessantly menaced by moving sand-hills, which surround it on every side, and would engulf it were it not for the continued struggle of man to arrest their progress.

[21] On 4 January 2005, seven civilian residents of Beit Lahia, including six members of the same family, were killed, with the incident blamed on shelling by Israel Defense Forces (IDF) of the agricultural area where they were working.

[citation needed] On 9 June 2006, eight civilians were killed by IDF shells while picnicking on the northern Gaza beach in Beit Lahia.

Around this time, the Gaza Soup Kitchen was established in Beit Lahia to provide food to Palestinians at risk of famine.

The Gaza Health Ministry reported over 90 casualties, including 25 children, with numerous individuals trapped under the rubble.