In fantasy, there are often weapons, especially swords of great heroes, with famous names and a dramatic backstory to them, such as Anduril, a blade only able to be wielded by the King of Gondor, or Dawn in Game of Thrones, with a fearsome reputation alongside the knight who carried it. In George Martin's Game of Thrones, the character Jaime Lannister even says "The best swords have names".
In mythology, there are also examples such as the famous sword Excalibur, or the weapons of the Norse Gods such as Mjölnir or Gungnir. But mythology is not history.
So, are there historical accounts of weapons with a famous name, wielded by great kings, staying in dynasties for generations as an heirloom, and the weapon itself earning a reputation, or is this just a fantasy trope inspired by mythology?
More can be written, but you might like to start with "Are named combat weapons a fantasy trope or are there records of named weapons being used in combat?" by /u/RockNRollJedi. There's also "How old is the tradition of naming weapons?" by /u/OMGSPACERUSSIA. There were other really famous historical named swords, but the answers mentioning them are just too brief for me to cite under current rules (blast it).
Edit for future use: "Was it a real thing to give names to weapons?"; /u/cnzmur wrote a wide-ranging discussion of Māori named weapons.
This is not to discourage discussion. More questions, data and debate are welcome.