They were the first European Garden Roses to have some China Rose genes. The third duchess of Portland brought from Italy in the year 1800 a repeating rose called "Rose Paestana.
From this rose the family of Portland Roses developed; roses that, apart from occasionally repeating, look like "Old Roses".
About 150 varieties of Portland Roses were introduced in the 19th century, most of them in France.
The last was "Rembrandt" by Moreau-Robert, in 1883. Very few Portland Roses are still in cultivation.