Which is the 'correct' version of "The Lady of Shalott" and why are there two?

Question

It seems Tennyson wrote two versions of "The Lady of Shalott". They are quite similar but have some big differences, for example, the first stanza of the 1832 version is:

On either side the river lie
Long fields of barley and of rye,
That clothe the wold and meet the sky;
And thro' the field the road runs by
      To many-tower'd Camelot;
The yellow-leaved waterlily
The green-sheathed daffodilly
Tremble in the water chilly
      Round about Shalott.

and the first stanza of the 1842 version is:

On either side the river lie
Long fields of barley and of rye,
That clothe the wold and meet the sky;
And thro' the field the road runs by
      To many-tower'd Camelot;
And up and down the people go,
Gazing where the lilies blow
Round an island there below,
      The island of Shalott.

Is the later one the final version of the original? Or are they two separate versions meant to both be different poems about the same subject?

Answer 1

The 1842 version is the more well-known version of this poem, and it most certainly is a revision of the first version. The University of Iowa (starting at "The Two Versions") conducted a thorough analysis of why Tennyson might have thought it necessary to make the changes he did. I'll give a rough summary, but many of the details are listed on that page.

Many of the reasons for the changes largely come down to Tennyson potentially wanting to change how the poetic observer sees Shalott. The 1833 version focuses much more on the natural environment, whereas the 1842 version seems to focus much more on Shalott itself. One of the examples that page uses is that:

The yellowleavèd waterlily,
The greensheathèd daffodilly,
Tremble in the water chilly,
Round about Shalott.

was replaced with:

And up and down the people go,
gazing where the lilies blow.

Later in the poem, Tennyson seems to want to insert more ambiguity about what, exactly, the story is surrounding her. The story becomes less straightforward, and what happens to her loses some definition in favor of narrative. The ultimate effect of this is to change the meaning and tonal feel of the ending of the piece.

There are a good deal more examples of this (which I won't repeat here - see the link above), and it does seem to be the primary reason for the edit.