diff --git a/apps/ingest/services.py b/apps/ingest/services.py
index 3af4ab6e..365283df 100644
--- a/apps/ingest/services.py
+++ b/apps/ingest/services.py
@@ -19,7 +19,10 @@ def clean_metadata(metadata):
     :rtype: dict
     """
     metadata = {key.casefold().replace(' ', '_'): value for key, value in metadata.items()}
-    fields = [f.name for f in Manifest._meta.get_fields()]
+    fields = [
+        *(f.name for f in Manifest._meta.get_fields()),
+        "related",  # used for related external links
+    ]
     invalid_keys = []
 
     for key in metadata.keys():
@@ -33,13 +36,31 @@ def clean_metadata(metadata):
         if key not in fields:
             invalid_keys.append(key)
 
+    # TODO: Update this method to allow all "invalid" keys to populate Manifest.metadata JSONField
     for invalid_key in invalid_keys:
         metadata.pop(invalid_key)
 
-
-
     return metadata
 
+def create_related_links(manifest, related_str):
+    """
+    Create RelatedLink objects from supplied related links string and associate each with supplied
+    Manifest. String should consist of semicolon-separated URLs.
+    :param manifest:
+    :type related_str: iiif.manifest.models.Manifest
+    :param related_str:
+    :type related_str: str
+    :rtype: None
+    """
+    for link in related_str.split(";"):
+        (format, _) = guess_type(link)
+        RelatedLink.objects.create(
+            manifest=manifest,
+            link=link,
+            format=format or "text/html",  # assume web page if MIME type cannot be determined
+            data_type="Document",  # assume this is not meant for seeAlso
+        )
+
 def create_manifest(ingest):
     """
     Create or update a Manifest from supplied metadata and images.
@@ -61,7 +82,13 @@ def create_manifest(ingest):
         else:
             manifest = Manifest.objects.create()
         for (key, value) in metadata.items():
-            setattr(manifest, key, value)
+            if key == "related":
+                # add RelatedLinks from metadata spreadsheet key "related"
+                create_related_links(manifest, value)
+            else:
+                # all other keys should exist as fields on Manifest (for now)
+                setattr(manifest, key, value)
+            # TODO: if the key doesn't exist on Manifest model, add it to Manifest.metadata
     else:
         manifest = Manifest()
 
@@ -77,9 +104,7 @@ def create_manifest(ingest):
         manifest.collections.set(ingest.collections.all())
         # Save again once relationship is set
         manifest.save()
-
-    # if type(ingest, .models.Remote):
-    if isinstance(ingest, Remote):
+    else:
         RelatedLink(
             manifest=manifest,
             link=ingest.remote_url,
diff --git a/apps/ingest/tasks.py b/apps/ingest/tasks.py
index 6b5458b2..91202aab 100644
--- a/apps/ingest/tasks.py
+++ b/apps/ingest/tasks.py
@@ -17,7 +17,7 @@
 from apps.ingest.models import IngestTaskWatcher
 
 from .mail import send_email_on_failure, send_email_on_success
-from .services import create_manifest
+from .services import create_manifest, create_related_links
 
 # Use `apps.get_model` to avoid circular import error. Because the parameters used to
 # create a background task have to be serializable, we can't just pass in the model object.
@@ -129,7 +129,12 @@ def create_canvases_from_s3_ingest(metadata, ingest_id):
     except Manifest.DoesNotExist:
         manifest = Manifest.objects.create(pid=pid)
     for (key, value) in metadata.items():
-        setattr(manifest, key, value)
+        if key == "related":
+            # add RelatedLinks from metadata spreadsheet key "related"
+            create_related_links(manifest, value)
+        else:
+            # all other keys should exist as fields on Manifest (for now)
+            setattr(manifest, key, value)
     # Image server: set from ingest
     ingest = S3Ingest.objects.get(pk=ingest_id)
     manifest.image_server = ingest.image_server
diff --git a/apps/ingest/tests/test_local.py b/apps/ingest/tests/test_local.py
index 2d7a0a4b..5cfdb6ca 100644
--- a/apps/ingest/tests/test_local.py
+++ b/apps/ingest/tests/test_local.py
@@ -331,6 +331,23 @@ def test_it_creates_mainfest_with_metadata_property(self):
         assert local.manifest.pid == '808'
         assert local.manifest.title == 'Goodie Mob'
 
+    def test_create_related_links(self):
+        metadata = {
+            'pid': '808',
+            'related': 'https://github.com/ecds/readux/tree/develop;https://archive.org/download/cherokeehymnbook00boud/cherokeehymnbook00boud.pdf'
+        }
+        local = self.mock_local('no_meta_file.zip', metadata=metadata)
+        local.manifest = create_manifest(local)
+        related_links = local.manifest.related_links
+        # should get 2 from metadata, 1 from volume url
+        assert len(related_links) == 3
+        # should get github link format as text/html
+        assert any([link["@id"] == "https://github.com/ecds/readux/tree/develop" for link in related_links])
+        assert any([link["format"] == "text/html" for link in related_links])
+        # should get pdf format too
+        assert any([link["@id"] == "https://archive.org/download/cherokeehymnbook00boud/cherokeehymnbook00boud.pdf" for link in related_links])
+        assert any([link["format"] == "application/pdf" for link in related_links])
+
     def test_moving_bulk_bundle_to_s3(self):
         """
         It should upload Local.bundle_from_bulk to mock S3 by saving it to