He said he needed the victims' cash to pay expenses so he could release the money from foreign bank accounts.
Graham also told unwitting clients, who were encouraged to invest large sums of money in a complex deal, that the United Nations owed him $13m for helping to restore democracy to an African country.
This week, Graham stunned his legal team when nine weeks into his trial, he suddenly admitted his guilt.
At Timaru District Court today he was jailed for three years and two months - a sentence which Judge Brian Callaghan said would bring some "closure" for Graham's victims.
The judge told Graham, standing in the dock with the aid of a walking stick: "Many New Zealanders, many of them elderly, were taken in by this ruse. You have robbed them of a comfortable retirement.
"The guilty pleas to the 99 charges will at least provide some closure."
From 1997 to 2007 he was a prolific international traveller, making more than 115 international flights, often first class.
Graham, who also uses the name Lin Graham, was arrested at Auckland airport in July 2009 as he was about flee the country to Singapore on a one-way ticket.
He was granted bail to a Christchurch address.
But prosecutor Tim Gresson said Graham continued to operate his fraudulent investment schemes while on bail.
He was arrested again shortly afterwards and charged with further offences.
There were several suitcases full of documented evidence of the charges, which included 43 counts of false pretences causing execution of valuable security, 15 counts of false pretences pecuring delivery of something capable of being stolen, 37 counts of deception causing loss, three counts of attempted deception, and one count of obtaining credit by deception.
The Crown said the amounts involved were "between $1.5m and $1.6m, possibly more" and over an estimated 10-year period.
The victims, who have been granted name suppression, largely came from the Oamaru and South Canterbury areas.
While most victims were elderly, Graham had also promised to finance the purchase of a $7m farm for a man in his 30s but said he would need an investment to gain access to foreign bank accounts. The farm was never purchased and the farmer eventually went bankrupt as a result.
One Oamaru woman met the accused and, with her husband, invested around $100,000 to get his "gold certificates authenticated" but they never received any cash back.
However, the woman also introduced an elderly family member in North Otago to the same scheme, and he agreed to invest $100,000 so funds could be released from Switzerland. It is thought he invested up to $400,000 up until January 2008.
Another elderly North Otago couple invested up to $260,000 over nine years. The couple was told their payments were used for bank fees, customs fees and to pay off corrupt bank officials.
An Oamaru couple in their 60s invested around $548,000.
Judge Callaghan said the victims were resigned to the fact they would not get any reparation.
Just $6270 was recovered by police but Judge Callaghan said he would not make a reparation order for that "insulting" amount.
He told Graham, who has already been in custody for 17 months, that he hoped he was aware of the victim's "hardships and betrayal" which he had caused.
