Holland ready to step out of Southgate's shadow in Japan
The 54-year-old was the right-hand man to Southgate during their eight years together with England, a period which saw them reach two European Championship finals and one World Cup semi-final.
Both men stepped down following England's defeat to Spain in the Euro final in Germany last year and Holland is now back in a job in Yokohama, following in the footsteps of Harry Kewell and Ange Postecoglou.
Holland also worked as an assistant at Chelsea for eight years but his only previous experience in charge of a team was at Crewe Alexandra between 2007 and 2008.
He said he was "very ambitious" about his managerial career and that he told Southgate soon after last year's Euro final that he wanted to strike out on his own.
"He came to my house and I made it quite clear to him that I wanted to be a head coach," Holland told reporters after leading Yokohama in training for the first time ahead of next month's J. League season opener.
"I also, out of respect for our relationship, wanted him to know early so that he had time to organise who his next assistant would be if he went into another job.
"I'm very happy to be here, this is a really exciting project, and I'm looking forward to getting cracking with the players this season," he added.
'Strong friendship'
Southgate, 54, has not worked since leaving the England job and has hinted he may not return to management.
Holland said he did not know what Southgate, who was given a knighthood in the New Year Honours, planned to do next.
"I speak with Gareth regularly, we have a really strong friendship," he said.
"I can't answer the question do I think he'll be in another job soon, I don't know the answer to that, you'd have to ask him."
Yokohama are part of City Football Group and were led by Postecoglou, who is now at Tottenham, from 2018 to 2021.
They finished last season ninth in the J. League and were beaten finalists in the Asian Champions League.
They started the season with former Liverpool and Leeds forward Kewell in the dugout but fired him midway through the campaign and put his assistant John Hutchinson in interim charge.
Holland said he was "very much looking forward to the opportunity that I've been given" in Japan.
"Being a head coach is something I'm very ambitious about doing, and I feel very well placed, given the experiences I've had to make that step," he said.