This is my problem, my recollection is vague but I believe the issue was 
with the Italian authorities and may have had something to do with 
"vexatious visit".  I did check in the Livy biography reference by 
Barbara but there, too, is only the mention of Roosevelt and U.S. Customs.

On 12/30/21 2:47 AM, Wolfgang Hochbruck wrote:
> Shipping deceased U.S. citizens back to the States can't have been 
> that difficult, or maybe it depended more on regulations in the 
> respective countries -- between ca. 1890 and the First World War, 
> there were more American consular offices f. i. in Germany than at any 
> other time in U.S. history. Freiburg had one. I did some research on 
> how the consul at the time, Theophilus Liefeld, helped Cora Crane to 
> get the mortal remains of Stephen back to the U.S. Funeral parlors 
> especially in places with a lot of tourist trade also specialised in 
> embalming and shipping. The only time Stephen Crane came to Freiburg, 
> it was feet first.
>
> best
>
> Wolfgang
>
> Prof. Dr. Wolfgang Hochbruck
> Department of English /
> Centre for Security and Society
> Albert Ludwigs University
> 15 Rempart St.
> D- 79098 Freiburg
>
> Am 30.12.2021 um 04:00 schrieb Scott Holmes:
>> I recall some mention of possible difficulties in returning Livy's 
>> body to the United States from Italy.  I have been unable to find a 
>> reference to the American ambassador, or someone of near his rank, 
>> clearing the way to ship her body as proper documentation had not 
>> been obtained. The remark that recurs in my mind is that such 
>> clearance was given because of Mark Twain's celebrity and that an 
>> ordinary person would have been stymied  and unable to send a body 
>> home again.
>>
>> The only reference to bureaucratic interference in Livy's death that 
>> I have been able to find is a mention in Day by Day "FLORENCE, June 
>> 7.—A funeral service of the simplest character took place over the 
>> body of Mrs. Samuel L. Clemens in the Villa Quarto to-day after a 
>> vexatious visit from sanitary officers and compliance with annoying 
>> regulations. Only members of the family were present."  There was no 
>> reference to this comment other than MTP.
>>
>> I'm working on an essay touching on Twain's relationship with 
>> bureaucracies and this instance seems an important encounter. There 
>> are many others but this one is what prompted me to consider this 
>> question.