One Piece's Elbaph Arc has slowly become the arc where not only are the Holy Knights' official character designs being unveiled, but new ones are also getting introduced. The latest additions include Siant Sommers and Killingham. While some fans might not notice this, the inspiration behind these new Holy Knights might be related to a real-life loyal lineage.
Shamrock, Sommers, and Killingham might be related to 'The King's Body Guard Of Yeomen Of Guard,' which includes the protectors of the highest British rulers. Surprisingly, the badges of this group, called the Heraldic Badges, have a namesake similarity with King Harald, potentially tying the Elbaph King to both the Holy Knights and Imu.
Disclaimer: This article contains potential spoilers from the manga series and expresses the author's opinion.
One Piece: Exploring the connection between King Harald and the Holy Knights

One Piece's Elbaph Arc began with the Straw Hat Pirates arriving on this island and sharing cups of sake with the giants to commemorate their friendship. However, the arc's start also introduced two Holy Knights who arrived on the island, hoping to affiliate it with the World Government. The two Holy Knights were Shamrock Figarland and Gunko.
After failing to come to terms with the accursed Prince Loki, the Holy Knights took another approach by kidnapping the Elbaph children. For this purpose, two more Holy Knights were called, namely Saint Sommers and Killingham. However, an odd thing about the encounter between these Holy Knights was the mention of King Herald.
Saint Killingham, after getting summoned to Elbaph Island, immediately asked Shamrock if he had arrived to visit King Harald's grave. While this might seem like a sarcastic question, it could also hint at a deeper secret. To decipher this, let's first look at the inspiration behind these Holy Knights.

Shamrock, as given by his name, might be inspired by the Shamrock flower (a type of clover). Similarly, Sommers is presumably inspired by roses, as displayed by his name's meaning linked to the Midsummer festivals. But what could be the inspiration behind Killingham? To the surprise of some fans, Killingham's inspiration might be given through the latter half of his name.
Saint Killingham might be inspired by Buckingham Palace, as both share the same suffix of 'ham.' The palace is the residence of the British Royals, but what might this reference indicate? The shamrock and rose flower are also related to Buckingham Palace, as they are together on the emblem of 'The King's Body Guard of Yeomen of Guard.'

This guard represents the highest order of knights directly affiliated with the royal palace. Interestingly, the crux of this entire article is that the badges of these guards are termed Heraldic Badges (meaning their association with a higher authority). However, in this case, a more interesting factor would be the mention of 'Harald' from One Piece in these badges (as in 'Herald').
So, given the above-established point from the newly introduced Holy Knights, King Harald from One Piece might be related to Shamrock and his fellow knights through their inspiration from the British Royal Guard.
Analysis and Final Thoughts
Harald's 'presumed' relationship with the Holy Knights might indicate numerous scenarios. Firstly, this relationship might indicate the King of Elbaph's association with the World Government and Imu, strengthening the fact that Loki may have killed his father.
Alternatively, King Harald might have been a rebel who betrayed the World Government after witnessing their corrupt standards. This might also make sense as to why Elbaph Island has never been associated with the World Government since King Harald took over.
Related Links
- One Piece chapter 1134 teases that Loki didn't kill King Harald
- Jarul, not Loki, may be the true Shame of Elbaph in One Piece
- Not just Big Mom's return, but also Kaido's is teased in One Piece