Ghazir's name is derived from Arabic root words for "heavy rains", and the town is known for its numerous groundwater reserves.

[5][6] According to Lebanese historian Kamal Salibi, the Mamluks' target in the Keserwan campaigns were the Alawite and Shia Muslims who dominated the region.

[6] Afterward, the Mamluks garrisoned troops in Ghazir under the command of Suleiman Ibn 'Arab to guard the sea route between Tabarja and the Nahr al-Kalb river.

[4] The garrisoned force consisted of Sunni Muslim Turkmen tribesmen,[6] who made Ghazir their headquarters in their ensuing feudal rivalry with the Druze Tanukh tribe that dominated southern Mount Lebanon.

[14] Throughout the rule of Emir Mansur Assaf (r. 1528–1579), he eliminated his Sunni and Shia Muslim rivals in northern Mount Lebanon and the Tripoli region, including a massacre of several Bedouin tribesmen from the Ibn al-Hansh at a reception in his Ghazir headquarters.

[15] Emir Mansur maintained policies favorable to the Maronite clans of northern Mount Lebanon, who he did not view to be as dangerous of a threat to his power as his Muslim rivals, and encouraged their resettlement of Keserwan.

[15] Among these Maronite clans were the Khazens and Gemayels, but Mansur developed particularly strong ties with the Hubaysh family, who settled in Ghazir itself in 1517–1518 and served as the 'Assaf's chief political agents.

[15] The 'Assaf emirs launched numerous building works in Ghazir, including the construction of a Serail on the site of the Convent of St. Francis, a mosque, bathhouses, hydraulic installations and gardens.

[19] Consequently, the newly appointed governor of Sidon Sanjak, of which Keserwan was part, attempted to oust the Sayfas, but his forces were repelled.

[20] Ahmad Ma'an, the ruler of the Mount Lebanon Emirate, appointed Talib and Turabay Hubaysh as the governors of Ghazir in 1670.

[22] The commander of the latter, Mahmoud Abi Harmush, pursued Haydar to Ghazir, attacking and plundering the town with the assistance of the Ottoman troops of Sidon Eyalet's governor,[22] Bashir Pasha al-Matarji.

As part of Emir Bashir's centralization and reorganization efforts in Mount Lebanon following his destruction of his erstwhile Druze allies' feudal power, he appointed a Maronite bishop as qadi (chief judge) and based him in Ghazir.

[27] The French writer and politician Édouard Lockroy spent a considerable amount of time in Ghazir where he befriended several of the town's residents.

However, the town and the Keserwan region in general saw an influx of Christians coming from other parts of Lebanon during the 1975–1990 Lebanese Civil War.

[4] The significant boom in the population during the civil war put a burden on the Ghazir Municipality's capabilities and led to major changes to the town's traditional architectural heritage, which had remained largely undisturbed through the 1960s.

In response, the Agency for Technical Cooperation and Development, with German and UN funding, built a reservoir in the town with a capacity of 1,000 cubed meters.

[4] However, other old traditional industries survive in Ghazir, including tapestry manufacturing, straw furniture-making, ironwork and wine and olive oil production.