I don't think it's clear at all that Ned didn't know that Lyanna went willingly. What is he supposed to do with that information? She's betrothed to Robert, the fact that she loves Rhaegar doesn't at all make it OK for her to up and leave, that's not how the world works. Robert was in love with her and wouldn't have heard a word about it. If you look at Ned's POV chapters in the books, his thoughts about Rhaegar don't seem like he bears him animosity.
Warning, book stuff from now on.
The Rebellion was only based on a lie if you buy the story that those Houses were totes loyal to the Targs, but wouldn't you know it, Rhaegar stole one of their women and unfortunately they have no choice but to go get her back. However, this is likely to be a whitewashing of history, the story is probably more complicated. There is a theory known in fandom as "Southron Ambitions", after this quote from Lady Dustin (a book-only character) talking to Theon:
Quote:
The day I learned that Brandon was to marry Catelyn Tully, though … there was nothing sweet about that pain. He never wanted her, I promise you that. He told me so, on our last night together … but Rickard Stark had great ambitions too. Southron ambitions that would not be served by having his heir marry the daughter of one of his own vassals.
What does she mean by this? Well, we know that the lords of Houses Tully, Baratheon, Stark, Arryn and perhaps Lannister were unusually close at this time, and the houses were linking themselves together with intermarriage. Ned and Robert were fostered together by Lord Arryn at the Eyrie. Catelyn was betrothed to Brandon Stark, Robert to Lyanna. Lord Hoster Tully sought to betroth his daughter to Jaime Lannister, possibly intending to bring them into the alliance, but Aerys II foiled this by naming Jaime to his Kingsguard.
This is all very unusual. If you look at Westerosi history, normally the children of Great Houses are betrothed to vassal houses, to strengthen the Great House's position with their bannermen. This heavy intermarriage between Great Houses is likely to be a sign that there was a conspiracy between at least 4 of them to wrest power from Aerys II. With the disappearance of dragons, Targaryen control over Westeros is not really backed by anything anymore. So the theory is that the Rebellion was coming anyway and that Lyanna eloping with Rhaegar provided a convenient excuse. There's more to the story, but that's a bare bones version.
Last edited by ChrisV; 05-25-2019 at 10:49 PM.