An individual from Poland who claimed to be the missing girl "pursued that myth" and stalked the missing girl's parents by sending emails, making phone calls and appearing at their address, a trial was told.
Karen Spragg and Julia Wandelt carried out a "systematic intimidation", the court was informed, and in Ms Wandelt's case, that lasted for two and a half years.
At the trial's commencement, the court heard Ms Wandelt consistently asserted she was the missing child and was taken and transported to Poland.
Ms Spragg and the second accused each deny a charge of harassment causing significant distress and distress to Kate and Gerry McCann between mid-2022 and early this year.
The child's vanishing in the year 2007 - at the age of three during a family holiday in the European country - is among the most extensively covered missing child cases and remains unsolved.
Legal counsel also mentioned the global attention that the disappearance had brought on the parents.
"One of many devastating outcomes for the McCann family has been their ongoing struggle to avoid the spotlight of media attention that came with that incident.
"The focus they have received has sometimes lacked sympathetic, sometimes far from it.
"There continues to exist a number of people who continue to fail to acknowledge their plight and perpetuate unfounded claims.
"Regrettably, these two defendants belong to that second category."
Increasing Actions
The court heard from mid-2022, the defendant had started telling to "anyone who would care to listen" that she was the missing child.
Legal authorities said that, in January 2023, Ms Wandelt was in contact with a organization in Poland established to assist with long-term disappearance incidents and provide assistance and guidance to people seeking those who had gone missing.
According to the prosecutor, Ms Wandelt first claimed she was the disappeared child Inga Gehricke.
But after these assertions were dismissed by the charity, Ms Wendalt then contacted the group with a belief she could be another missing child - a disappeared infant from Utah in the US - before messaging them about her persistent claim she was Madeleine McCann.
'Did Not Deter'
The defendant's conviction progressed to an effort to contact the medical facility where the parents were employed.
A lengthy telephone conversation to the reception resulted in a notification from the NHS trust's communications manager to the investigation team, the British investigation into the vanishing.
The jury was told the defendant made additional efforts to reach out to officials and then the father directly via email in mid-2023.
In one email, she stated: "It's possible I am your child, there's a chance I am the missing girl."
She continued people were "trying to cover up the case" and asserted there were similarities between her and the child, including having scars in the identical locations.
But her attempts went unanswered, which court officials said "did not deter" Ms Wendelt - who then made contact with Madeleine's younger sister the sibling via social media.
Informing her she was her "only hope", she sent doctored images to show they were "possibly connected" and asserted possessing recollections of life before the abduction, the trial was told.
These assertions, the proceedings revealed, were restated in this year when Ms Wendalt is alleged to have "repeatedly" messaged Mrs McCann's mobile over the course of a day - referring to her as "mother", asserting memory of giving food to Madeleine's younger brother Sean, of engaging in ring a roses in the back garden of the family's home in Rothley, Leicestershire, and of the night the disappearance occurred.
In one message, she stated: "I recall you came to my bedroom before the abduction, touched my hair and said 'I love you and I'll locate you'."
Court proceedings of Ms Wendalt, of Jana Kochanowskiego in Lubin, the country, and Ms Spragg, of a location in the Welsh city, proceeds.
