‘And the Lord gave Jehoiakim, king of Judah, into his hand, with part of the vessels of the house of God. And he carried them into the land of Shinar to the house of his god, and he brought the vessels into the treasure house of his god.'
The siege was sufficiently fierce to enable him to persuade Jehoiakim to make submission, possibly by offering milder terms. He was bought off with part of the temple treasures, taking with him selected young men, possibly as hostages for good behaviour.
Note that it was ‘the Lord' (adonai) who caused the submission of Jehoiakim. He it was Who was in charge of overall events. It was not that Yahweh was defeated, Nebuchadnezzar was as much subject to His will as Jehoiakim.
The vessels taken were carried off to the ‘land of Shinar', an ancient name for Babylonia (Genesis 10:8-10; Genesis 11:1-9), reflecting its belligerence and idolatry. There they were put in the house of his favourite god, probably Marduk, in the treasure house. Treasure houses were regularly connected with temples. The treasures would be placed there as a thankoffering to the god for giving victory, but would still be available to the king.