The only one that comes to mind right now is english ivy. Not sure how you feel about using that but it stays evergreen here (central Maryland, Zone 7)

Hey! I suggest a real winner. It's an evergreen vine reaching 4-5 meters, hardy to at least 10 degrees F, and extremely attractive. This jewel is Clematis armandii(Franch). Here in central Virginia it is difficult to find, but I should think that any near-by horticultural garden will allow you to take a cutting. In the early stages it grows rapidly: the flowers are insignificant, the leaves are 20-30cm X 5-7cm. Good Luck!

'the flowers are insignificant' Well, no it's not one of those huge dinnerplate cultivars but to call them insignificant I would contest. It produces very large clusters of beautifully scented flowers early in the year (it's the earliest to bloom here except for C. balearica)But it's only hardy to -5C so might not survive in the OP's area. Here's a link for you to decide the insignificance of the flowers.

Here is a link that might be useful:

I agree with flora - I would hardly consider the flowering of C. armandii to be "insignificant". As with most species clematis, the flowers are smaller than the hybrids but are produced in massive quantities, virtually covering the vine and obscuring the foliage when in full, early spring bloom. And unless in a protected location, I also doubt this would do well in the OP's location as it will not be tolerant of single digit temps and experience a lot of winter dieback.

English ivy is obviously out of the question anywhere in Oregon :-) The list of evergreen flowering vines is limited for even very mild areas and decreases rapidly in colder zones. I'd consider crossvine, Bignonia capreolata, or Carolina jessamine, Gelsemium sempervirens. Both are hardy to zone 6, perhaps lower.

Just for the record; Bignonia capreolata L. has been renamed.It is currently Anisostichus capreolata (L) Bureau.It retains leaves even at 5 degrees F. and has stunning orange-yellow flowers. A fine choice for Gardengal!

Euonymus fortunei 'Emerald Gaiety' is a variegated evergreen that tinges pink in winter. Susceptible to scale and spider mites if kept too dry, although somewhat drought tolerant. Can be used as a vine or a groundcover.

Here is a link that might be useful: Euonymus fortunei 'Emerald Gaiety'

Now that the herbaceous perennials are dying back the evergreens are showing up again. It was nice to see 'Emerald Gaiety' had grown a bit more this summer, but is so slow to climb the hummingbird trellis in my part sun location. I am tempted to give up & move that trellis elsewhere for another climber in more sunshine.

absolutely agree that C. armandi is beautiful and has been wonderful here in S. Jersey, zone 7a. A very brief bloom of beautifully scented flowers.
Another good evergreen is Gelsemium sempervirens, which blooms briefly with slightly scented flowers for me here. Leaves turn purple with strong Sun.
Would recommend nursery called Brushwood Nursery. Website might be gardenvines.com. They are in SE PA, I think.