This is supported by the fact that this card has 100 less ATK and DEF than "High Laundsallyn" does, as well as the fact that "High Laundsallyn" wields two swords in his artwork, both red-colored versions of "Noble Arms - Arfeudutyr" and "Noble Arms - Excaliburn".
This knight is based on the Arthurian knight Lancelot du Lac, also known as the White Knight, who is most famous for his betrayal of King Arthur through his love affair with Arthur's wife, Queen Guinevere. The juxtaposition of his title with the infamous deed is referenced in the card's Japanese name.
As such, the lake in this card's artwork may be a reference to the residence of Lancelot's adoptive mother, the Lady of the Lake.
This is even further supported by the fact that "Ignoble Knight of High Laundsallyn" wields the sword that "Lady of the Lake" is carrying in her artwork: "Noble Arms - Excaliburn".
This card's ability to obtain a "Noble Arms" card from your Deck is likely a reference to the other event Lancelot is most famous for: searching for the Holy Grail.