From Monarchists.Wiki

Jehosheba (Hebrew: יְהוֹשֶׁ֫בַע), also known as Jehoshabeath (Hebrew: יְהוֹשַׁבְעַת), was the wife of the priest Jehoiada and a daughter of King Jehoram of Judah.

Her father married Princess Athaliah of Israel. Athaliah is traditionally considered to be the daughter of King Ahab of Israel and Jezebel; thus, she continued in their wicked ways (i.e. the worship of Baal) and spread them to Judah. Jehoram and Athaliah conceived, and Athaliah gave birth to Jehosheba's half-brother Ahaziah. When Jehoram died, Athaliah's son Ahaziah inherited the throne of Judah. Athaliah advised her son and encouraged him to act wickedly.

After Jehu slew Ahaziah, Athaliah massacred all of the royal contenders she could find and usurped the throne of Judah for herself. Unbeknownst to Athaliah, Jehosheba managed to save and hide Ahaziah's sole surviving son (thus, Ahaziah's rightful heir) Jehoash.

In the seventh year of Athaliah's illegitimate reign, Jehosheba's husband and priest Jehoiada gathered many guard and bodyguard captains together and formed a pack with them in Jehoash's favor. They then anointed Jehoash as the rightful King of Judah. This was followed by shouts of Long live the king, trumpets, and jubilation.

Athaliah heard the commotion and personally went to investigate. After realizing what was occurring, Athaliah shouted, Treason! Treason! Jehoiada and those loyal to the King then captured and executed her.

Jehoiada then restored the covenant between God, king, and the people of Judah, and the people destroyed the temple of Baal and executed Baal's priest, putting an end to the wickedness Athaliah brought to Judah.