This might be called the central message of Second Isaiah. "The LORD is God, and there is no other" turns out to be not merely an abstract theological assertion, but a gracious promise: since God alone is Lord, all can turn to God for deliverance and salvation.
God is the savior of Israel, of course; so, throughout, this book makes clear that the exiles will be brought back to Jerusalem from all the ends of the earth (see 43:4-7; 49:8-12; 60:4-10). But some passages in Isaiah, like this one, make clear that God summons and saves the nations as well. From the beginning, God chose Israel in order to bless the nations (Genesis 12:1-3), and now God will use the fact of Israel's dispersal among the nations to reach out to the nations for their good.
22 Turn to me and be saved,
all the ends of the earth!
For I am God, and there is no other.
New Revised Standard Version Bible: Anglicized Edition, copyright © 1989, 1995 National Council of the Churches of Christ in the United States of America. Used by permission. All rights reserved worldwide. http://nrsvbibles.org