In the first 32 lines of Alfred Lord Tennyson's "Ulysses," written in 1833, the poet is taking on the guise of the hero musing to himself. In the first five lines, the hero appears bored with post-adventure life on Ithaca. In lines 6-32, he reflects upon his past adventures at Troy and on his return home to Ithaca. Next, at lines 33-44, Ulysses turns his attention to his son Telemachus and imagines the sort of ruler that his son will be once he is gone.
In the final part of the poem, Ulysses address his fellow sailors. At line 45, he calls them "my mariners"; at line 49 he links himself with them in age ("you and I are old"); and at lines 56-57 he says, "Come, my friends / 'Tis not too late to seek a newer world." He summons them to further adventures and journies.
Of course, Tennyson's "real" addressee for this poem is most likely his fellow British countrymen, whom he is reminding of their glorious past and urging them on to a more glorious future.