How to I assign an item or an order to a location via API when creating an order?

[APIANT]

The location that appears above each item:

I tried the Origin location ID but it doesn't seem to work

[APIANT]

Is this how to do this?:

Create a simple order and fulfill it

POST /admin/api/2020-01/orders.json
{
  "order": {
    "email": "foo@example.com",
    "fulfillment_status": "fulfilled",
    "fulfillments": [
      {
        "location_id": 48752903
      }
    ],
    "line_items": [
      {
        "variant_id": 447654529,
        "quantity": 1
      }
    ]
  }
}

[APIANT · Accepted solution]

Here's the solution. After creating the order, fetch the order, the the fulfillment order IDs (if there is more than one location assigned) and move each item to the appropriate location using the Move fulfillment order endpoint: