diff --git a/google-cloud-errors/test/google/cloud/errors/gapic_rest_errors_test.rb b/google-cloud-errors/test/google/cloud/errors/gapic_rest_errors_test.rb
new file mode 100644
index 000000000000..b9e1c4460146
--- /dev/null
+++ b/google-cloud-errors/test/google/cloud/errors/gapic_rest_errors_test.rb
@@ -0,0 +1,84 @@
+# Copyright 2024 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+require "helper"
+require "google/cloud/errors"
+require "grpc/errors"
+require "google/gax/errors"
+require "google/rpc/status_pb"
+
+# These test confirm that REST exceptions corresponding to various HTTP status codes
+# are correctly wrapped
+describe Google::Cloud::Error, :rest_errors do
+  it "identifies CanceledError" do
+    mapped_error = wrapped_rest_error gapic_rest_error(status_code: 499)
+    _(mapped_error).must_be_kind_of Google::Cloud::CanceledError
+  end
+
+  it "identifies InvalidArgumentError" do
+    mapped_error = wrapped_rest_error gapic_rest_error(status_code: 400)
+    _(mapped_error).must_be_kind_of Google::Cloud::InvalidArgumentError
+  end
+
+  it "identifies DeadlineExceededError" do
+    mapped_error = wrapped_rest_error gapic_rest_error(status_code: 504)
+    _(mapped_error).must_be_kind_of Google::Cloud::DeadlineExceededError
+  end
+
+  it "identifies NotFoundError" do
+    mapped_error = wrapped_rest_error gapic_rest_error(status_code: 404)
+    _(mapped_error).must_be_kind_of Google::Cloud::NotFoundError
+  end
+
+  it "identifies AlreadyExistsError" do
+    mapped_error = wrapped_rest_error gapic_rest_error(status_code: 409)
+    _(mapped_error).must_be_kind_of Google::Cloud::AlreadyExistsError
+  end
+
+  it "identifies PermissionDeniedError" do
+    mapped_error = wrapped_rest_error gapic_rest_error(status_code: 403)
+    _(mapped_error).must_be_kind_of Google::Cloud::PermissionDeniedError
+  end
+
+  it "identifies ResourceExhaustedError" do
+    mapped_error = wrapped_rest_error gapic_rest_error(status_code: 429)
+    _(mapped_error).must_be_kind_of Google::Cloud::ResourceExhaustedError
+  end
+
+  it "identifies FailedPreconditionError" do
+    mapped_error = wrapped_rest_error gapic_rest_error(status_code: 412)
+    _(mapped_error).must_be_kind_of Google::Cloud::FailedPreconditionError
+  end
+
+  it "identifies UnimplementedError" do
+    mapped_error = wrapped_rest_error gapic_rest_error(status_code: 501)
+    _(mapped_error).must_be_kind_of Google::Cloud::UnimplementedError
+  end
+
+  it "identifies InternalError" do
+    mapped_error = wrapped_rest_error gapic_rest_error(status_code: 500)
+    _(mapped_error).must_be_kind_of Google::Cloud::InternalError
+  end
+
+  it "identifies UnavailableError" do
+    mapped_error = wrapped_rest_error gapic_rest_error(status_code: 503)
+    _(mapped_error).must_be_kind_of Google::Cloud::UnavailableError
+  end
+
+  it "identifies unknown error" do
+    # We don't know what to map this error case to
+    mapped_error = wrapped_rest_error gapic_rest_error(status_code: 0)
+    _(mapped_error).must_be_kind_of Google::Cloud::Error
+  end
+end
diff --git a/google-cloud-errors/test/google/cloud/errors/wrapped_gapic_rest_test.rb b/google-cloud-errors/test/google/cloud/errors/wrapped_gapic_rest_test.rb
new file mode 100644
index 000000000000..1deca9dc7b7b
--- /dev/null
+++ b/google-cloud-errors/test/google/cloud/errors/wrapped_gapic_rest_test.rb
@@ -0,0 +1,37 @@
+# Copyright 2020 Google LLC
+#
+# Licensed under the Apache License, Version 2.0  the "License";
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+require "helper"
+require "google/cloud/errors"
+require "grpc/errors"
+require "google/gax/errors"
+require "google/rpc/status_pb"
+
+describe Google::Cloud::Error, :wrapped_rest_error do
+  # This test confirms that a whole array of any-wrapped detail messages
+  # containing various messages from the `google/rpc/error_details.proto`
+  # will be correctly deserialized and surfaced to the end-user
+  # in the `status_details` field when wrapping the rest error
+  it "contains multiple detail messages" do
+    error = wrapped_rest_error gapic_rest_error(status_code: 404, extended_details: true)
+
+    di = error.status_details.find {|entry| entry.is_a?(Google::Rpc::DebugInfo)} 
+    _(di).must_equal debug_info
+
+    lm = error.status_details.find {|entry| entry.is_a?(Google::Rpc::LocalizedMessage)} 
+    _(lm).must_equal localized_message
+
+    help_detail = error.status_details.find {|entry| entry.is_a?(Google::Rpc::Help)} 
+  end
+end
diff --git a/google-cloud-errors/test/google/cloud/errors/wrapped_gax_test.rb b/google-cloud-errors/test/google/cloud/errors/wrapped_gax_test.rb
index 6e54ef693463..f4ef1f9edaf6 100644
--- a/google-cloud-errors/test/google/cloud/errors/wrapped_gax_test.rb
+++ b/google-cloud-errors/test/google/cloud/errors/wrapped_gax_test.rb
@@ -19,43 +19,13 @@
 require "google/rpc/status_pb"
 
 describe Google::Cloud::Error, :wrapped_gax do
-  def debug_info
-    Google::Rpc::DebugInfo.new detail: "status_detail"
-  end
-
-  def error_info
-    Google::Rpc::ErrorInfo.new reason: "ErrorInfo reason", domain: "ErrorInfo domain", metadata: {"foo": "bar"}
-  end
-
-  def localized_message
-    Google::Rpc::LocalizedMessage.new locale: "fr-CH", message: "c'est un message d'erreur"
-  end
-
-  def help
-    link = Google::Rpc::Help::Link.new description: "example description", url: "https://example.com/error"
-    Google::Rpc::Help.new links: [link]
-  end
-
   ##
   # Construct a new Google::Rpc::Status object and return its binary encoding
   #
   # @param extended_details [Boolean] 
   #    Whether to encode multiple error details. Default is one DebugInfo message.
   def encoded_protobuf extended_details: false
-    any_debug = Google::Protobuf::Any.new
-    any_debug.pack debug_info
-
-    any_message = Google::Protobuf::Any.new
-    any_message.pack localized_message
-
-    any_help = Google::Protobuf::Any.new
-    any_help.pack help
-
-    status_arr = [any_debug]
-    status_arr = [any_debug, any_message, any_help] if extended_details
-
-    status = Google::Rpc::Status.new details: status_arr
-
+    status = google_rpc_status extended_details: extended_details
     Google::Rpc::Status.encode status
   end
 
diff --git a/google-cloud-errors/test/helper.rb b/google-cloud-errors/test/helper.rb
index 1e50e2e2bc39..2b982c9df5c0 100644
--- a/google-cloud-errors/test/helper.rb
+++ b/google-cloud-errors/test/helper.rb
@@ -20,3 +20,121 @@
 require "minitest/rg"
 require "json"
 require "google/cloud/errors"
+require "grpc/errors"
+require "google/rpc/status_pb"
+
+def debug_info
+  Google::Rpc::DebugInfo.new detail: "status_detail"
+end
+
+def error_info
+  Google::Rpc::ErrorInfo.new reason: "ErrorInfo reason", domain: "ErrorInfo domain", metadata: {"foo": "bar"}
+end
+
+def localized_message
+  Google::Rpc::LocalizedMessage.new locale: "fr-CH", message: "c'est un message d'erreur"
+end
+
+def help
+  link = Google::Rpc::Help::Link.new description: "example description", url: "https://example.com/error"
+  Google::Rpc::Help.new links: [link]
+end
+
+def google_rpc_status extended_details: false
+  any_debug = Google::Protobuf::Any.new
+  any_debug.pack debug_info
+
+  any_message = Google::Protobuf::Any.new
+  any_message.pack localized_message
+
+  any_help = Google::Protobuf::Any.new
+  any_help.pack help
+
+  status_arr = [any_debug]
+  status_arr = [any_debug, any_message, any_help] if extended_details
+
+  Google::Rpc::Status.new details: status_arr
+end
+
+def gapic_rest_error status_code:, extended_details: false
+  status = google_rpc_status(extended_details: extended_details).to_json
+  jp = JSON.parse(status)
+  details = jp["details"]
+
+  headers = {"content-type" => "application/json; charset=UTF-8", "content-encoding"=>"gzip"}
+
+  gapic_rest_err = MockGapicRestError.new(
+    :status => "err_message for #{status_code}",
+    :details => details,
+    :status_code => status_code,
+    :headers => headers
+  )
+
+  gapic_rest_err
+end
+
+def wrapped_rest_error gapic_rest_error
+  begin
+    begin
+      raise gapic_rest_error
+    rescue => gapic_r_e
+      raise Google::Cloud::Error.from_error gapic_r_e
+    end
+  rescue => e
+    return e
+  end
+end
+
+##
+# A truncated copy of gapic-common's GapicRestError that only keeps the 
+# parse details decoding implementation.
+# Here to avoid referencing gapic-common.
+#
+class MockGapicRestError < StandardError
+  attr_reader :status_code, :status, :details, :headers
+  alias status_details details
+
+  def initialize msg = nil
+    super
+  end
+
+  def initialize status_code:, status:, details:, headers:
+    @status_code = status_code
+    @status = status
+    @msg = status
+    @details = parse_details details
+    @headers = headers
+
+    super
+  end
+
+  ##
+  # A copy of implementation from gapic-common's GapicRestError
+  #
+  def parse_details details
+    # For rest errors details will contain json representations of `Protobuf.Any`
+    # decoded into hashes. If it's not an array, of its elements are not hashes,
+    # it's some other case
+    return details unless details.is_a? ::Array
+    
+    details.map do |detail_instance|
+      next detail_instance unless detail_instance.is_a? ::Hash
+      # Next, parse detail_instance into a Proto message.
+      # There are three possible issues for the JSON->Any->message parsing
+      # - json decoding fails
+      # - the json belongs to a proto message type we don't know about
+      # - any unpacking fails
+      # If we hit any of these three issues we'll just return the original hash
+      begin
+        any = ::Google::Protobuf::Any.decode_json detail_instance.to_json
+        klass = ::Google::Protobuf::DescriptorPool.generated_pool.lookup(any.type_name)&.msgclass
+        next detail_instance if klass.nil?
+        unpack = any.unpack klass
+        next detail_instance if unpack.nil?
+        unpack
+      rescue ::Google::Protobuf::ParseError
+        detail_instance
+      end
+    end.compact
+  end
+end